[dmitrii-f-t27]

Closes #13208

Closes dmitrii-f-t27#19

Workspace acceptance spec

Changes

• Preserve the release toolchain and inherited PATH order while finding locally installed clients from a GUI launch.
• Add persisted workspace bindings, stable task tabs, and two independently routed native terminal panes. Starting, restarting, and stopping a pane are explicit actions.
• Add workspace-scoped PTY lookup, attach, and I/O while retaining the legacy SPAWN and LIST wire formats.

Verification

• 279 focused t27b tests passed across workspace, protocol, window, PATH, and VT specs. Five workspace specs passed the t27c and Zig seal sequence. The conformance validator accepted all 111 vector files.
• The native daemon matched 27 portable wire vectors. Lookup and reattach preserved pane IDs and process count. An older daemon refused the new requests and still returned the legacy LIST frame.
• An isolated macOS run launched installed OpenCode from the native workspace UI with a system-only inherited PATH. Two bound projects preserved their pane IDs and processes across workspace switches and an app-only reopen. Two simultaneous panes passed input isolation, resize, scrollback, copy, and editor-return checks.
• A binding-only native C-to-D rebind updated the saved row while all packed metadata stayed unchanged. An app-only reopen retained the new binding and unrelated live pane identities.
• Provider login and paid model requests were outside the native acceptance run.

Dmitrii Fedorov (@dmitrii-f-t27)

[dmitrii-f-t27]

@gHashTag could you coordinate the upstream fixes for two baseline checks that block this PR? Both recur at head b1ff85388 against base f451395a3.

• duplicate-bodies expects the bytes_eq group sizes [11, 3] and reports [12, 3]. All 15 files in those groups are byte-identical to the base, including specs/tri/t27b/timeout_terminal.t27. The exact base run reports the same counts.
• scan scans the full tree and flags the existing developer-home literal in that same unchanged file. This PR adds no matching literal. The exact base run flags the same file.

Both issue-traceability checks now pass with upstream issue #13208. The workspace patch leaves the baseline files and branch checks unchanged.

A later Documented t27c subcommands exist run reports 71 dead tri mentions against the limit of 68. This patch changes no CLI command implementation or scanned documentation. The exact base run reports the same 68-to-71 failure.

Dmitrii Fedorov (@dmitrii-f-t27)

[dmitrii-f-t27]

Refreshed onto master 085f0d7 (merge 080fcf8). Only the four pty seal JSONs conflicted; they were regenerated with t27c built from 085f0d7, never hand-merged. Tests on the merged tree: workspace_tasks 9/9, pty_proto 12/12, pty_client 3/3, pty_logic 61/61, keys 115/115, t27b glass_window and pty_server 0 failed.

Native acceptance from workspace_tasks.t27 run in the app window (local build 7983 = master + this PR + #13339, launched from Finder): split a task and typed separately in both panes; the PATH fix found installed opencode and claude from a GUI launch; switched projects and back with both panes restored; closed and reopened the window: the same server and the same three pane processes reattached, no duplicate launch; closed an earlier task after stopping its panes explicitly, the later task survived. Binding fixture folders through the system folder dialog was not exercised; discovered spaces were used. The pane-table overlap with 12+ panes is fixed on master by #13351. Out of draft.

@gHashTag please merge when CI is green.

Dmitrii Fedorov (@dmitrii-f-t27)