Audit mobile resume query refetch policy

[ymichael]

Summary

• defines the query reconnect rules in docs/research/mobile-resume-query-refetch-audit.md: websocket-reconnect invalidation is for realtime-owned query families only; no websocket reconnect invalidation for focus-owned live reads, static/session reads, expensive/manual reads, observer-less eviction caches, or typeahead/ephemeral queries
• resolves the previously suspicious items instead of leaving follow-ups: queued messages, host file previews, host provider CLI status, system usage limits, duplicate thread default execution hooks, and the queued-message dependency on PR Keep active thread state consistent after browser resume #439 behavior
• adds tests for the changed policies and keeps the audit table current with concrete keep/fix decisions

Resolved policy decisions

Item	Resolution
threadQueuedMessages	Fixed: now refetches stale queue data on focus/pageshow, matching threadTimeline instead of relying on PR #439-specific behavior.
threadHostFilePreview	Fixed: added canonical prefix helpers, focus/reconnect refetch, and websocket-reconnect catch-up invalidation.
hostProviderCliStatus	Fixed as focus-owned, not websocket-owned: 60s stale window plus focus/network-reconnect refetch. Websocket reconnect is not a semantic CLI dirty event.
systemUsageLimits	Fixed as focus-owned, not websocket-owned: mounted Settings refreshes on focus/network reconnect with the existing 30s stale window; manual refresh remains.
Duplicate useThreadDefaultExecutionOptions	Fixed: removed the legacy hook from thread-queries.ts; the dedicated hook reuses canonical query keys. The no-focus policy remains intentional because these values seed visible composer controls and should not churn draft defaults on focus.
Terminal and automation queries	Fixed: added websocket-reconnect catch-up invalidation for realtime-owned terminal and automation families.

Validation

• pnpm exec turbo run test --filter=@bb/app 165 files / 1114 tests passed
• pnpm exec turbo run typecheck --filter=@bb/app
• git diff --check