Fix Quick Chat workspace chrome

[coneilen]

Summary

Fix the Windows Quick Chat workspace so dismissing a chat cannot restore its chat-scoped workspace or the previous loop's bar and panel when workspace toggles are used. Refs #774.

Changes

• Show Quick Chat-specific workspace chrome and keep loop-only panels/actions out of chat workspaces while preserving the chat's agent pane.
• Carry chat creation time through the model and create new chats with a date-stamped title and configured default backend.
• Clear the chat workspace binding only after dismissal successfully resets to the current graph; prevent either workspace toggle from resurfacing a chat-bound workspace after a reset failure, and restore ordinary workspace behavior on project/node selection.
• Match macOS Restart-session behavior: LoopWorkspaceLoopBar.swift:112-113 paints the button for unresolved nodes, while AppFeature+LoopSessions.swift:105-107 intentionally does nothing for Quick Chats. Windows paints and publishes the workspace-restart-session- UIA action; it is a visible no-op for chats, as documented by macOS: Quick Chat loop bar shows a Restart session button that does nothing #804.
• Add workspace-binding, UIA/protocol, timestamp, and native Restart-session UIA regressions. The empty Quick Chats canvas/CTA remains deferred to lane B and is not claimed by this PR.
• Restore the current-main GraphCanvas.loopDetailSparklineBounds and GraphCanvas.loopDetailFooterBounds accessibility geometry after the rebase regression.

Test plan

RED: zig.exe test src\App.zig --test-filter "opening a quick chat after a loop workspace selects the chat bar through its UIA item" on origin/main -> expected chat-1, found loop-a; 0 passed, 1 failed (behavioral).
GREEN: & $env:GRAPHCODE_ZIG0152 test src\App.zig src\AccessibilityProvider.cpp src\FilePicker.c src\FolderPicker.c C:\gcp\d2\winghostty\zig-out\lib\winghostty-win32-host.lib -DUNICODE -D_UNICODE -target x86_64-windows-msvc -lc -luser32 -lgdi32 -lgdiplus -lmsimg32 -lopengl32 -lkernel32 -limm32 -lole32 -loleaut32 -luiautomationcore -lshell32 -ladvapi32 -lwinhttp -IC:\gcp\d2\winghostty\include zig-out\lib\ghostty-vt-static.lib --cache-dir C:\gcs\d2\postpush-focused\cache --global-cache-dir C:\gcs\d2\postpush-focused\global-cache --test-filter "quick chat workspace" -> 2/2 passed on 29b4e3e.
REGRESSION: & $env:GRAPHCODE_ZIG0152 test src\App.zig src\AccessibilityProvider.cpp src\FilePicker.c src\FolderPicker.c C:\gcp\d2\winghostty\zig-out\lib\winghostty-win32-host.lib -DUNICODE -D_UNICODE -target x86_64-windows-msvc -lc -luser32 -lgdi32 -lgdiplus -lmsimg32 -lopengl32 -lkernel32 -limm32 -lole32 -loleaut32 -luiautomationcore -lshell32 -ladvapi32 -lwinhttp -IC:\gcp\d2\winghostty\include zig-out\lib\ghostty-vt-static.lib --cache-dir C:\gcs\d2\postpush-focused\cache --global-cache-dir C:\gcs\d2\postpush-focused\global-cache --test-filter "DPI UIA" -> 3/3 passed on 29b4e3e.

The same App test root and pinned dependencies passed with --test-filter "chat-bound workspace" (1/1) and --test-filter "loop detail UIA rectangles" (1/1), also on 29b4e3e. Logs: C:\gcs\d2\postpush-focused\quick-chat.log, chat-bound.log, loop-detail.log, and dpi-uia.log.

The native Restart-session contract test was run before and after the provider AutomationId mapping: RED was 208 checks with 2 expected failures (missing stable AutomationId and canvas-card-count invariant); GREEN was 208 checks, 0 failures. Exact-head shard-0 CI is pending after this push and will exercise the test wired by #802.

The last desktop full-unit run was on 624bff1: 1201/1201 tests and 55/55 sections completed, but the command exited 1 only because the #802 harness cleanup hit a Remove-Item race. #805 fixes that cleanup path; a current-head full -ShellPart unit run is still pending its desktop slot and is not claimed as passing.

Not verified

• Exact-head CI for 29b4e3e is still queued; no current-head CI result is claimed yet.
• The existing paired capture from 624bff1 remains applicable to the chat-bar pixels because this workspace-binding fix does not change Quick Chat painting, so no recapture is indicated for this commit. That capture's Agent-tab assertion failed and its pane remained at “Opening quick chat...”; it does not establish persisted daemon launch or agent attachment.
• A current-head full -ShellPart unit run inside a desktop slot remains pending. The previous run's default-profile guard used a process-scoped scratch profile and the real-folder validation root C:\gc-d2.
• The native contract test has local RED/GREEN evidence above; its current-head shard-0 CI result is pending.
• The earlier local WorktreeGitProcess case=removals failure remains unattributed. A later run passed that case under the real C:\gc-d2 root, but that does not establish the earlier failure's cause.
• make test and make check were not run; they are macOS validation commands and do not cover this Windows change.
• Persisted daemon Quick Chat startup and agent attachment remain unverified; this PR does not claim either behavior.

Checklist

• I have read the Contributing Guidelines
• I have signed off my commits (git commit -s) per the DCO
• Tests pass locally (make test)
• Code follows the existing style (make check)
• I added the test/contract before the implementation and observed the intended RED failure

[coneilen]

Closed unmerged by operator decision (2026-10-14). Wave 1 was stopped and is being restarted from current main under a revised process: exact-head CI as the regression gate, screenshots taken once at the end, and escalation only after 5 failed iterations. This PR's findings are recorded on the issue. Superseded by the wave-2 PR for the same issue.