* feat(models): unify provider metadata around backend catalog
- Move shared provider metadata and alias normalization into backend-owned provider catalog
- Expose display, fetch, auth, and default model metadata through /api/models provider_options
- Replace frontend static provider registry with catalog-driven selection, validation, grouping, and fallback rendering
- Treat provider default api_base as placeholder and effective fetch/test base while keep submitted api_base separate from derived defaults
- Add model page retry handling, touched locale updates, and provider metadata assertions in backend tests
* fix(models): canonicalize backend provider aliases and common models
* fix(models): restore deepseek common model recommendations
* feat(web,api): add fetch models and saved catalog support
Split from PR #2752 (part 2 of 3).
Backend:
- /api/models/catalog endpoint for browsing remote model catalogs
- /api/models/fetch endpoint for fetching available models from providers
- Credential reuse with provider/API base matching for security
- Default API base resolution for providers without explicit base
Frontend:
- FetchModelsDialog for importing models from remote providers
- CatalogDialog for browsing and importing from model catalogs
- Static import for FetchModelsDialog (replaces dynamic import from PR1)
- Dynamic import retained for TestModelDialog (PR3 territory)
* fix(web,api): support bare-array responses in fetchOpenAICompatibleModels
* fix(web,api): tighten maskAPIKeyValue to match maskAPIKey policy
For 9-12 character keys, maskAPIKeyValue exposed first 4 + last 4
chars (only 1 char masked for a 9-char key). Now uses the same
policy as maskAPIKey: first 3 + last 2 for 9-12 chars, first 3 +
last 4 for longer keys. Adds tests covering all key length boundaries.
LC