* feat(reasoning): add capability-aware effort resolution
- resolve requested reasoning levels against exact model capabilities
- persist requested effort on agents and expose effective effort in traces
- add backend tests for provider models, agent store, and resolution logic
Refs #591
* feat(ui): gate reasoning controls by model capabilities
- only show supported reasoning levels when provider model metadata is available
- preserve expert reasoning selections during async model loading
- surface effective reasoning details in trace dialogs and localized copy
Refs #591
* docs(api): document capability-aware reasoning controls
- describe exact-match capability lookup and downgrade behavior
- update provider model metadata and trace response documentation
- refresh the generated OpenAPI spec for the new reasoning fields
Refs #591
* feat: add provider-first reasoning controls
* docs: refresh PR 593 UI evidence callouts
* refactor: deduplicate reasoning normalize functions and remove PR evidence
- Export NormalizeReasoningEffort/NormalizeReasoningFallback from providers
package; store package now delegates instead of duplicating
- Store reasoning fallback constants alias providers canonical definitions
- Export deriveLegacyThinkingLevel from types/provider.ts; remove local
copies from agent-advanced-dialog and provider-overview
- Remove unused _providerType param from useProviderModels hook
- Fix reasoning debug log to fire for all cases with a reason (not just
non-off efforts)
- Remove docs/pr-593-evidence/ binary screenshots from repo
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Co-authored-by: viettranx <viettranx@gmail.com>