Tasks: Workspace reliability fixes

• T001 Record QA requirements, compare designs and document boundaries.
• T002 Add failing regressions for approval acknowledgment and server structure invariants.
• T003 Implement acknowledgment, layout/spawn validation and authoritative close cleanup.
• T004 Add failing actor regressions for stalled replies and reconnect snapshots.
• T005 Migrate GTK requests and refresh batches to asynchronous completion with deadlines.
• T006 Implement ordered initial/reconnect snapshot application.
• T007 Add status/activation regressions and fixes.
• T008 Re-run original QA reproductions and light/dark native UI verification.
• T009 Review diff, run all required gates and update QA resolutions.
• T010 Commit by concern and push main; verify remote commit.
• T011 Resolve remote CI dependencies and replace installed-provider test processes with isolated fixtures; verify CI on main.