[shaohaozhi286]

Adds a browser action to HTML/HTM source previews, opening the saved local file in a session-owned ACECode browser tab with encoded file:// paths and the existing unsaved-file guard. Integrates completed prompt-cache/context persistence, parent-model inheritance, keyboard shortcut settings, channel icon/layout improvements and the sidebar update entry for v1.0.0.

Validation: Web tests/build, i18n catalog, focused HTML browser fixture, strict OpenSpec and static checks passed. Windows Release and MinSizeRel builds passed. Full Windows run: 6,170 executed, 6,161 passed, 9 skipped, 0 failures (plus one pre-existing disabled test). First run had seven timed-wait failures while compiling concurrently; all passed in the complete idle rerun without changing assertions. Publication remains gated on Linux CI and final package verification.

Release audit: 46 worktrees examined in the fixed 2026-10-06 00:52:50 through 2026-10-08 00:52:50 Asia/Taipei window. The recent Agent Office HEAD is already an ancestor of master. Nine explicitly retained migration refs are preserved. Related changes: open-html-preview-in-browser, stabilize-prompt-cache-prefix, add-keyboard-shortcuts-and-compact-channels.

Validation capture:

HTML fixture: keyboard navigation, encoded file URL, session owner, unsaved cancel/save, error paths PASS
profile=full shards=3 inventory=6171 executed=6170 skipped=9 failed=0 not_run=0
strict layer findings: 0