Feat/sidebar files panel

[kevincodex1]

Summary

Adds a FILES section to the TUI's right context sidebar (between PLAN and ACTIVITY) showing the workspace files the session has touched — newest first, with an A/M/✗ status badge, an aggregated +added −removed diffstat per file, a pulsing row for the file whose write is streaming right now, and a +N more overflow trailer.

Clicking a row selects the file (accent ▸ on the row, its edit cards tint in the chat, transcript scrolls to the most recent one; Esc clears). A second click opens a drill-in view reusing the subchat pattern: the chat column swaps to the file's stacked full-depth edit cards (edit N of M); f toggles to the syntax-highlighted on-disk file with ▎ markers on session-added lines, d back to diff, Esc returns to the chat at its saved scroll position.

The roster has two data sources: changedFiles carried by write_file/edit_file/apply_patch results (persisted to the session payload, so the panel survives /resume), and a git sweep for mutations the tool stream can't see — agents that scaffold via exec_command/bash or delegate to subagents. A baseline git status --porcelain --untracked-files=all snapshot at startup hides pre-existing dirt; re-sweeps after each command-tool result and at turn end merge newly dirty paths with a git diff HEAD --numstat diffstat. Sweeps are single-flight, 3s-timeboxed, and latch off in non-git workspaces.

Implementation notes: the drill-in swaps the body inside transcriptBodyItems and replaces the pinned title bar with a one-line nav, so the scroll engine, viewport, and mouse hit-testing stay consistent with no special-casing; the selection tint is part of the render-cache key so stale cards can't be served; FILES renders below PLAN so existing plan-step click offsets are untouched.

Linked issuediffstat per file, a pulsing row for the file whose write is streaming right now, and a +N more overflow trailer.

Clicking a row selects the file (accent ▸ on the row, its edit cards tint in the chat, transcript scrolls to the most recent one; Esc clears). A second click opens a drill-in view reusing the subchat pattern: the chat column swaps to the file's stacked full-depth edit cards (edit N of M); f toggles to the syntax-highlighted on-disk file with ▎ markers on session-added lines, d back to diff, Esc returns to the chat at its saved scroll position.

The roster has two data sources: changedFiles carried by write_file/edit_file/apply_patch results (persisted to the session payload, so the panel survives /resume), and a git sweep for mutations the tool stream can't see — agents that scaffold via exec_command/bash or delegate to subagents. A baseline git status --porcelain --untracked-files=all snapshot at startup hides pre-existing dirt; re-sweeps after each command-tool result and at turn end merge newly dirty paths with a git diff HEAD --numstat diffstat. Sweeps are single-flight, 3s-timeboxed, and latch off in non-git workspaces.

Implementation notes: the drill-in swaps the body inside transcriptBodyItems and replaces the pinned title bar with a one-line nav, so the scroll engine, viewport, and mouse hit-testing stay consistent with no special-casing; the selection tint is part of the render-cache key so stale cards can't be served; FILES renders below PLAN so existing plan-step click offsets are untouched.

Checklist

• The linked issue already has the issue-approved label.
• go build ./..., go vet ./..., and go test ./... pass locally.
• gofmt clean.
• Tests added/updated for the change (and run under -race where relevant). — 22 new tests across files_panel_test.go, file_view_test.go, files_git_sweep_test.go (incl. a sweep test against a real temp git repo); go test -race ./internal/tui/ passes.
• UI changes include screenshots or a short recording where possible. — terminal captures below.

Summary by CodeRabbit

• New Features

  • Added a new FILES sidebar section that shows recently touched files, including change counts and a compact overflow indicator.
  • Added a drill-in file viewer with diff and full file modes, plus easy switching while viewing a file.
  • File rows now highlight related edits and support hovering/clicking for faster navigation.

• Bug Fixes

  • Improved detection of file changes so more workspace edits appear in the sidebar.
  • Preserved scroll position and selection behavior when opening, closing, or switching file views.

[coderabbitai]

Walkthrough

Adds a FILES sidebar section aggregating files touched by tool results and a git status sweep, a drill-in file view with diff/full rendering modes, hover and click wiring, render-cache/tint updates for selected files, and supporting transcriptRow.changedFiles data plumbing, with accompanying unit tests.

Changes

FILES sidebar and file drill-in feature

Layer / File(s)	Summary
changedFiles data plumbing internal/tui/transcript.go, internal/tui/session.go, internal/tui/model.go	Adds changedFiles []string to transcriptRow, populated live from tool results and rehydrated from session payloads via a new payloadStringSlice decoder.
Git sweep detection internal/tui/files_git_sweep.go, internal/tui/files_git_sweep_test.go, internal/tui/model.go	Adds gitSweepCmd running git status --porcelain and git diff --numstat, parsing/baseline logic, gating via maybeGitSweep, and message handling in the model, with unit and real-repo tests.
Touched files aggregation and sidebar internal/tui/files_panel.go, internal/tui/files_panel_test.go, internal/tui/sidebar.go, internal/tui/model.go	Builds a touchedFiles() roster from transcript rows and git sweep results, renders the FILES sidebar section with badges/diffstats/pulse row, computes clickable hit regions, and supports file selection/scroll-to-card.
Hover and selection tint internal/tui/hover.go, internal/tui/sidebar.go, internal/tui/render_cache.go, internal/tui/rendering.go	Adds hoverFileRow hover kind, sidebar hover offset mapping, and border tinting plus render-cache key updates for rows touching the selected file.
File drill-in view internal/tui/file_view.go, internal/tui/file_view_test.go, internal/tui/files_git_sweep_test.go	Implements fileViewState, open/exit/mode-switch lifecycle, nav bar, diff-mode edit-card rendering, full-mode on-disk rendering with gutter markers, and changed-line parsing.
Model wiring for file view internal/tui/model.go, internal/tui/transcript_selection.go	Wires key handling (d/f toggle, Esc exit), pinned title bar swap, transcript body swap, and closes the file view before subchat/plan-step navigation.

Estimated code review effort: 4 (Complex) | ~60 minutes

Possibly related PRs

• Gitlawb/zero#83: Both PRs modify the TUI's transcript-row/tool-result metadata and card rendering pipeline that the file-view/diff-mode relies on.
• Gitlawb/zero#300: Both PRs modify the two-column context sidebar plumbing that the FILES-sidebar drill-in builds on.
• Gitlawb/zero#350: Both PRs modify the TUI hover system, with this PR extending hover prioritization for FILES rows.

Suggested reviewers: Vasanthdev2004, gnanam1990

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title is clearly related to the main change: adding a FILES sidebar panel.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

---

_{Comment @coderabbitai help to get the list of available commands.}

[coderabbitai]

Actionable comments posted: 3

🧹 Nitpick comments (3)

internal/tui/file_view_test.go (1)

99-134: 📐 Maintainability & Code Quality | 🔵 Trivial | ⚡ Quick win

No coverage for the fileViewMaxLines truncation path.

TestFileViewFullBody covers a 2-line file; there's no test asserting that a file exceeding fileViewMaxLines actually gets truncated with the "… N more lines" trailer. Given the unbounded-read concern flagged in file_view.go, a regression test here would both document intent and catch it if the read path changes.

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@internal/tui/file_view_test.go` around lines 99 - 134, Add a regression test
around TestFileViewFullBody that exercises the truncation branch in
renderFileViewFull: create a file with more than fileViewMaxLines lines, open it
through openFileView and setFileViewMode(fileViewFull), then assert the rendered
output ends with the “... N more lines” trailer and only includes up to
fileViewMaxLines visible lines. Use the existing fileViewMaxLines and
renderFileViewFull symbols so the test documents and protects the truncation
behavior.

internal/tui/file_view.go (1)

209-224: 🎯 Functional Correctness | 🔵 Trivial | ⚡ Quick win

Trimmed-text matching will over-mark common lines.

fileViewChangedLines keys on trimmed line text across the whole file, so any short/common added line (}, return nil, blank-after-trim, etc.) will also mark every identical pre-existing line elsewhere in the file — for curly-brace-heavy code this could light up unrelated lines throughout the file, diluting the signal the gutter marker is meant to give. The doc comment already flags this as an accepted approximation, so this is a nice-to-have rather than a blocker — e.g. skipping trivial/very-short lines from the changed set would cut most of the noise cheaply.

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@internal/tui/file_view.go` around lines 209 - 224, The current
fileViewChangedLines approximation is too broad because it keys on trimmed text,
so common short additions like braces or return nil can over-mark unrelated
lines in fileViewResultRows. Update fileViewChangedLines to avoid adding
trivial/very-short trimmed lines to the changed set, keeping the gutter markers
focused on meaningful additions while preserving the existing plus-line
filtering logic.

internal/tui/transcript_selection.go (1)

1271-1281: 📐 Maintainability & Code Quality | 🔵 Trivial | ⚡ Quick win

Consider adding tests for the FILES click-routing logic.

This branch adds new click-state logic (select vs. open/switch based on fileView.active/selectedFile), and the sibling exitFileView()-before-navigation additions (Lines 1253, 1266) codify an important mutual-exclusion invariant. No test coverage for handleTranscriptSelectionMouse accompanies this layer's files. Given the branching complexity (first-click-select vs. click-while-open vs. click-on-selected), a few table-driven cases would guard against regressions here.

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@internal/tui/transcript_selection.go` around lines 1271 - 1281, The new FILES
click-routing branch in handleTranscriptSelectionMouse needs test coverage to
lock in the select-vs-open behavior. Add table-driven tests around
handleTranscriptSelectionMouse (and, if needed,
fileRowAtMouse/selectFile/openFileView) covering first click on an unselected
file, click on the already-selected file, and any click while fileView.active is
true. Also verify the mutual-exclusion behavior introduced by exitFileView()
before navigation by asserting the expected state transitions and returned
actions.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@internal/tui/files_git_sweep_test.go`:
- Line 173: Replace the literal nil Context passed to gitSweepCmd in the git
sweep tests with a real context instance to satisfy SA1012. Update each affected
call site in the test code to use a proper Context value, and add the context
import in the test file so the existing gitSweepCmd helper still receives a
valid context argument.
- Around line 37-45: The TestParseGitNumstat case is using a rename string that
does not match real `git diff --numstat` output, so it is not exercising the
actual rename parsing path. Update the test data in `TestParseGitNumstat` to use
a real numstat rename format (for example the `=>` style that `parseGitNumstat`
should handle, including brace-compressed renames if relevant) and keep the
existing assertions aligned with the `parseGitNumstat` behavior so the rename
case is properly covered.

In `@internal/tui/files_git_sweep.go`:
- Around line 121-142: `parseGitNumstat` is using the wrong rename format, so
renamed files from `git diff --numstat` keep a mismatched path and end up with
zeroed diffstat. Update `parseGitNumstat` to recognize numstat rename paths that
use ` => ` (including brace-compressed forms) instead of relying only on
`cutRename`, and normalize the resulting path before storing it in `stats`. Also
adjust the related test coverage so it uses the real numstat rename shape,
ensuring the lookup in `gitSweepCmd` matches the porcelain-derived file path.

---

Nitpick comments:
In `@internal/tui/file_view_test.go`:
- Around line 99-134: Add a regression test around TestFileViewFullBody that
exercises the truncation branch in renderFileViewFull: create a file with more
than fileViewMaxLines lines, open it through openFileView and
setFileViewMode(fileViewFull), then assert the rendered output ends with the
“... N more lines” trailer and only includes up to fileViewMaxLines visible
lines. Use the existing fileViewMaxLines and renderFileViewFull symbols so the
test documents and protects the truncation behavior.

In `@internal/tui/file_view.go`:
- Around line 209-224: The current fileViewChangedLines approximation is too
broad because it keys on trimmed text, so common short additions like braces or
return nil can over-mark unrelated lines in fileViewResultRows. Update
fileViewChangedLines to avoid adding trivial/very-short trimmed lines to the
changed set, keeping the gutter markers focused on meaningful additions while
preserving the existing plus-line filtering logic.

In `@internal/tui/transcript_selection.go`:
- Around line 1271-1281: The new FILES click-routing branch in
handleTranscriptSelectionMouse needs test coverage to lock in the select-vs-open
behavior. Add table-driven tests around handleTranscriptSelectionMouse (and, if
needed, fileRowAtMouse/selectFile/openFileView) covering first click on an
unselected file, click on the already-selected file, and any click while
fileView.active is true. Also verify the mutual-exclusion behavior introduced by
exitFileView() before navigation by asserting the expected state transitions and
returned actions.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: b8ecc461-5025-435d-bf4d-f28dc54fd3b8

📥 Commits

Reviewing files that changed from the base of the PR and between 02f0c09 and 1fdbcc0.

📒 Files selected for processing (14)

• internal/tui/file_view.go
• internal/tui/file_view_test.go
• internal/tui/files_git_sweep.go
• internal/tui/files_git_sweep_test.go
• internal/tui/files_panel.go
• internal/tui/files_panel_test.go
• internal/tui/hover.go
• internal/tui/model.go
• internal/tui/render_cache.go
• internal/tui/rendering.go
• internal/tui/session.go
• internal/tui/sidebar.go
• internal/tui/transcript.go
• internal/tui/transcript_selection.go

[coderabbitai]

🎯 Functional Correctness | 🟠 Major | ⚡ Quick win

Rename test doesn't exercise real numstat format.

Complements the parseGitNumstat finding in files_git_sweep.go: this line uses " -> " (porcelain's delimiter) inside a numstat-shaped string, which isn't how git diff --numstat actually renders renames (" => ", optionally brace-compressed). Worth replacing with a case that matches real numstat output once the parser is fixed, so the rename path is actually covered.

-	stats := parseGitNumstat("12\t3\tweb/app.js\n-\t-\tassets/logo.png\n4\t0\told.go => pkg/new.go\n1\t1\tR\told.go -> pkg/new.go\n")
+	stats := parseGitNumstat("12\t3\tweb/app.js\n-\t-\tassets/logo.png\n4\t0\told.go => pkg/new.go\n2\t1\tsrc/{old.js => new.js}\n")
+	if got := stats["pkg/new.go"]; got != [2]int{4, 0} {
+		t.Errorf("renamed file = %v, want [4 0]", got)
+	}
+	if got := stats["src/new.js"]; got != [2]int{2, 1} {
+		t.Errorf("brace-compressed rename = %v, want [2 1]", got)
+	}

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	func TestParseGitNumstat(t *testing.T) {
	stats := parseGitNumstat("12\t3\tweb/app.js\n-\t-\tassets/logo.png\n4\t0\told.go => pkg/new.go\n1\t1\tR\told.go -> pkg/new.go\n")
	if got := stats["web/app.js"]; got != [2]int{12, 3} {
	t.Errorf("web/app.js = %v, want [12 3]", got)
	}
	if _, ok := stats["assets/logo.png"]; ok {
	t.Error("binary '-' entries must be skipped")
	}
	}
	func TestParseGitNumstat(t *testing.T) {
	stats := parseGitNumstat("12\t3\tweb/app.js\n-\t-\tassets/logo.png\n4\t0\told.go => pkg/new.go\n2\t1\tsrc/{old.js => new.js}\n")
	if got := stats["web/app.js"]; got != [2]int{12, 3} {
	t.Errorf("web/app.js = %v, want [12 3]", got)
	}
	if _, ok := stats["assets/logo.png"]; ok {
	t.Error("binary '-' entries must be skipped")
	}
	if got := stats["pkg/new.go"]; got != [2]int{4, 0} {
	t.Errorf("renamed file = %v, want [4 [0]]", got)
	}
	if got := stats["src/new.js"]; got != [2]int{2, 1} {
	t.Errorf("brace-compressed rename = %v, want [2 1]", got)
	}
	}

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@internal/tui/files_git_sweep_test.go` around lines 37 - 45, The
TestParseGitNumstat case is using a rename string that does not match real `git
diff --numstat` output, so it is not exercising the actual rename parsing path.
Update the test data in `TestParseGitNumstat` to use a real numstat rename
format (for example the `=>` style that `parseGitNumstat` should handle,
including brace-compressed renames if relevant) and keep the existing assertions
aligned with the `parseGitNumstat` behavior so the rename case is properly
covered.

[coderabbitai]

📐 Maintainability & Code Quality | 🟡 Minor | ⚡ Quick win

Pass a real context instead of nil (SA1012).

Static analysis flags gitSweepCmd(nil, ...) at these three call sites. gitSweepCmd itself tolerates it (substitutes context.Background()), but staticcheck's own guidance is to never pass a literal nil Context.

🔧 Proposed fix

-	baseline := gitSweepCmd(nil, dir, true)().(gitSweepMsg)
+	baseline := gitSweepCmd(context.Background(), dir, true)().(gitSweepMsg)
...
-	sweep := gitSweepCmd(nil, dir, false)().(gitSweepMsg)
+	sweep := gitSweepCmd(context.Background(), dir, false)().(gitSweepMsg)
...
-	if msg := gitSweepCmd(nil, t.TempDir(), false)().(gitSweepMsg); msg.ok {
+	if msg := gitSweepCmd(context.Background(), t.TempDir(), false)().(gitSweepMsg); msg.ok {

(needs "context" added to the import block)

Also applies to: 182-182, 198-198

🧰 Tools

🪛 golangci-lint (2.12.2)

[error] 173-173: SA1012: do not pass a nil Context, even if a function permits it; pass context.TODO if you are unsure about which Context to use

(staticcheck)

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@internal/tui/files_git_sweep_test.go` at line 173, Replace the literal nil
Context passed to gitSweepCmd in the git sweep tests with a real context
instance to satisfy SA1012. Update each affected call site in the test code to
use a proper Context value, and add the context import in the test file so the
existing gitSweepCmd helper still receives a valid context argument.

Source: Linters/SAST tools

[coderabbitai]

🎯 Functional Correctness | 🟡 Minor | ⚡ Quick win

parseGitNumstat never resolves real rename lines — diffstat for renamed files silently stays 0/0.

git diff --numstat renders renames with " => " (optionally brace-compressed, e.g. src/{old.js => new.js}), not the " -> " that git status --porcelain uses. cutRename here only recognizes " -> ", so a real numstat rename line like "12\t3\told.go => pkg/new.go" never matches: path stays the whole raw string, and stats["old.go => pkg/new.go"] never lines up with the porcelain-derived files[i].path ("pkg/new.go") used for the lookup in gitSweepCmd. The result is a silently wrong (zeroed) diffstat for any renamed-and-modified file the sweep discovers — not a crash, but it undermines the diffstat this section exists to show.

Worth noting the accompanying test doesn't catch this: it fabricates "1\t1\tR\told.go -> pkg/new.go" (using " -> ", which isn't how numstat actually formats renames) to force cutRename to fire, rather than testing the real " => " shape.

🔧 Proposed fix: recognize numstat's own rename delimiter

+// cutNumstatRename resolves `git diff --numstat`'s rename shape, either the
+// full "old => new" form or the brace-compressed "dir/{old => new}/tail" form.
+func cutNumstatRename(path string) string {
+	if start := strings.Index(path, "{"); start >= 0 {
+		if end := strings.Index(path[start:], "}"); end >= 0 {
+			end += start
+			if arrow := strings.Index(path[start:end], " => "); arrow >= 0 {
+				arrow += start
+				return path[:start] + path[arrow+4:end] + path[end+1:]
+			}
+		}
+	}
+	if idx := strings.Index(path, " => "); idx >= 0 {
+		return path[idx+4:]
+	}
+	return path
+}
+
 func parseGitNumstat(out string) map[string][2]int {
 	stats := map[string][2]int{}
 	for _, line := range strings.Split(out, "\n") {
 		parts := strings.SplitN(line, "\t", 3)
 		if len(parts) != 3 {
 			continue
 		}
 		adds, errA := strconv.Atoi(parts[0])
 		dels, errD := strconv.Atoi(parts[1])
 		if errA != nil || errD != nil {
 			continue
 		}
-		path := parts[2]
-		if to, _, found := cutRename(path); found {
-			path = to
-		}
-		stats[unquoteGitPath(path)] = [2]int{adds, dels}
+		path := cutNumstatRename(parts[2])
+		stats[unquoteGitPath(path)] = [2]int{adds, dels}
 	}
 	return stats
 }

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	// parseGitNumstat parses `git diff --numstat` output ("added\tdeleted\tpath")
	// into path → [added, deleted]. Binary files report "-" and are skipped.
	func parseGitNumstat(out string) map[string][2]int {
	stats := map[string][2]int{}
	for _, line := range strings.Split(out, "\n") {
	parts := strings.SplitN(line, "\t", 3)
	if len(parts) != 3 {
	continue
	}
	adds, errA := strconv.Atoi(parts[0])
	dels, errD := strconv.Atoi(parts[1])
	if errA != nil || errD != nil {
	continue
	}
	path := parts[2]
	if to, _, found := cutRename(path); found {
	path = to
	}
	stats[unquoteGitPath(path)] = [2]int{adds, dels}
	}
	return stats
	}
	// cutNumstatRename resolves `git diff --numstat`'s rename shape, either the
	// full "old => new" form or the brace-compressed "dir/{old => new}/tail" form.
	func cutNumstatRename(path string) string {
	if start := strings.Index(path, "{"); start >= 0 {
	if end := strings.Index(path[start:], "}"); end >= 0 {
	end += start
	if arrow := strings.Index(path[start:end], " => "); arrow >= 0 {
	arrow += start
	return path[:start] + path[arrow+4:end] + path[end+1:]
	}
	}
	}
	if idx := strings.Index(path, " => "); idx >= 0 {
	return path[idx+4:]
	}
	return path
	}
	// parseGitNumstat parses `git diff --numstat` output ("added\tdeleted\tpath")
	// into path → [added, deleted]. Binary files report "-" and are skipped.
	func parseGitNumstat(out string) map[string][2]int {
	stats := map[string][2]int{}
	for _, line := range strings.Split(out, "\n") {
	parts := strings.SplitN(line, "\t", 3)
	if len(parts) != 3 {
	continue
	}
	adds, errA := strconv.Atoi(parts[0])
	dels, errD := strconv.Atoi(parts[1])
	if errA != nil || errD != nil {
	continue
	}
	path := cutNumstatRename(parts[2])
	stats[unquoteGitPath(path)] = [2]int{adds, dels}
	}
	return stats
	}

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@internal/tui/files_git_sweep.go` around lines 121 - 142, `parseGitNumstat` is
using the wrong rename format, so renamed files from `git diff --numstat` keep a
mismatched path and end up with zeroed diffstat. Update `parseGitNumstat` to
recognize numstat rename paths that use ` => ` (including brace-compressed
forms) instead of relying only on `cutRename`, and normalize the resulting path
before storing it in `stats`. Also adjust the related test coverage so it uses
the real numstat rename shape, ensuring the lookup in `gitSweepCmd` matches the
porcelain-derived file path.