fix(source-control): signal worktree-create lock failure with exit 5

plugins/source-control/.claude-plugin/plugin.json

@@ -1,7 +1,7 @@
 {
   "$schema": "https://json.schemastore.org/claude-code-plugin-manifest.json",
   "name": "source-control",
-  "version": "0.53.4",
+  "version": "0.53.5",
   "description": "Git and GitHub delivery workflow: /commit (Conventional Commits + Co-Authored-By trailer via safe heredoc mechanics), /pull-request (prep, create, CI monitoring, review-comment triage, merge, CI-log fetch), /babysit-prs (self-pacing fleet loop \u2014 safe by default; opt-in worker/autopilot tiers add gate-checked merge and thread resolution behind a deterministic Python engine), /babysit-loop (the loop-lane merge lane: a standing or drain loop that invokes babysit-prs per cycle, configured through repo-scoped babysit_loop_* keys on the layered source-control.md seam, with merge authority human-only until the target repo's tracked config adopts the lane, a gate-proven C2-mechanical baseline once adopted, and standing merge-rung raises binding from the team-tracked layer only \u2014 with one named exception, where an invocation line explicitly typing both the autopilot tier keyword and the dedicated raise argument --merge c3-this-run widens that single invocation's merge authority up to C3 behind a fresh independent frontier-tier resolver, while C4-structural and C5-untrusted-provenance stay unconditionally human-merge), /worktree (create, status, cleanup, audit for parallel-session isolation), /setup (check the effective commit-subject / PR-title convention merged across its config layers and the babysit-prs config, or apply \u2014 interview the repo and write the convention config to a chosen layer), and /resolve-conflicts (intent-first merge/rebase conflict resolution with a semantic-conflict sweep \u2014 never --abort). The commit-subject / PR-title convention is configurable via a source-control.md config written by a re-runnable setup skill, layered across a ~/.claude user-global file, the tracked team file, and a gitignored .claude/source-control.local.md personal overlay merged per key; Conventional Commits is the default when no convention is declared.",
   "author": {
     "name": "Melodic Software",

plugins/source-control/CHANGELOG.md

@@ -3,6 +3,14 @@
 All notable changes to the `source-control` plugin are documented here. Format follows
 [Keep a Changelog](https://keepachangelog.com/en/1.1.0/); this plugin uses semantic versioning.
 
+## [0.53.5]
+
+### Fixed
+
+- **`worktree-create.sh` signals lock failure with exit 5 and `lock_failed=1` on stderr (#2389).** The
+  worktree path is still printed so orchestrators can detect an unarmed liveness guard without
+  treating a silent success as a locked worktree.
+
 ## [0.53.4]
 
 ### Changed

plugins/source-control/scripts/worktree-create.sh

@@ -665,8 +665,11 @@ fi
 # absent (#2257). The owning lane (or cleanup, after explicit confirmation)
 # disarms with `git worktree unlock <path>`.
 lock_reason="worktree-create.sh: lane active on ${HOSTNAME:-$(hostname 2>/dev/null || printf 'unknown-host')} since $(date -u +%Y-%m-%dT%H:%M:%SZ); unlock when the owning lane is done"
+lock_failed=0
 if ! git -C "$toplevel" worktree lock --reason "$lock_reason" "$worktree_path" >&2; then
+  lock_failed=1
   printf '%s: warning: could not lock the new worktree — cleanup sweeps will not see it as claimed\n' "$PROG" >&2
+  printf '%s: lock_failed=1\n' "$PROG" >&2
 fi
 
 # Reimplement Claude Code's .worktreeinclude copy: files that match a
@@ -703,3 +706,6 @@ fi
 
 printf '%s: created worktree on branch %q (base %s)\n' "$PROG" "$name" "$base_ref" >&2
 printf '%s\n' "$worktree_path"
+if ((lock_failed)); then
+  exit 5
+fi