- Fix refresh loop: proper while loop with 30s sleep and force:true
  instead of single-fire Task that never repeated
- Fix loading overlay: counter-based isLoading so concurrent fetches
  don't flicker the overlay on/off
- Fix rapid tab switching: cancel previous switchTask, check
  Task.isCancelled after CLI returns to discard stale results
- Fix tab strip vs hero desync: fetch provider-specific and all-provider
  data in parallel so costs arrive from same data snapshot
- Fix stale menubar icon after wake: forceRefresh now fetches today/all
  in parallel alongside the current selection
- Fix accent color: ThemeState is now @observable so color changes
  propagate via observation, removing .id() view hierarchy teardown
- Fix currency flash: defer store.currency and symbol update until a
  rate is available so symbol and rate apply atomically
- Fix export: terminationHandler instead of waitUntilExit (no UI freeze),
  HHmmss in filename to prevent overwrite on double-export
- Fix CurrencyState: @mainactor isolation with proper Sendable
  conformance, nonisolated on pure static functions
- Fix streak count: iterate calendar days instead of sparse history
  entries so gaps are counted as streak-breakers
- Fix TrendBar identity: stable date-based id instead of UUID
- Add GPT-5.3 and DeepSeek model display names