Added a warning about the development branch and Jellyfin support.

When upgrading from pre-Jellyfin versions, media_server_type is null.
Instead of defaulting to Plex everywhere (which caused noisy errors if
Plex was down), auto-detect the server type from existing credentials
during settings init and persist it.

- settings.service.ts: auto-detect Jellyfin/Plex from credentials on init
- media-server.factory.ts: throw instead of defaulting to Plex when
  no server type is configured; distinguish "not configured" from
  "unreachable" in startup logging
- collections.service.ts: update return type to match factory change

Query parameters are received as strings. Without ParseIntPipe, numeric
comparisons and math operations work on strings, producing incorrect results.

Added ParseIntPipe with optional: true to:
- media-server.controller.ts: page, limit parameters
- plex-api-legacy.controller.ts: amount parameter
- rules.controller.ts: rulegroupId, typeId parameters

Also refactored rules.controller.ts to use individual @query parameters
instead of inline object types for better type safety.

The Plex adapter's resetMetadataCache() was a no-op despite PlexApiService
having this capability. Now properly delegates to plexApi.resetMetadataCache()
when an itemId is provided.

Instead of hardcoding progress to 100, use the actual PlayedPercentage
from Jellyfin's UserData when available. Falls back to 100 if not set.

Note: Plex API doesn't expose progress percentage in watch history,
so it remains hardcoded to 100 (which is correct for completed watches).

The testResult state was never cleared when URL or API key inputs changed.
Users could modify credentials and save with a stale success indicator.
Now clears test result and testedSettings when credentials are modified.

The factory already handled errors properly, but the warning message
didn't include the actual error details for debugging. Now includes
the error message in the log output.

Remove leftover debug console.log statement from addImportExclusion.

Add comprehensive unit tests for PlexAdapterService covering:
- Lifecycle management (isSetup, initialize, uninitialize)
- Server type identification (returns PLEX)
- Feature detection (LABELS, PLAYLISTS, COLLECTION_VISIBILITY, etc.)
- Cache management with resetMetadataCache delegation
- Server status mapping to MediaServerStatus
- User fetching and mapping to MediaUser
- Library fetching and mapping to MediaLibrary
- Library content queries with Jellyfin ID detection
- Watch history retrieval and mapping to WatchRecord
- Collection operations (create, delete)
- Search content delegation

This brings the test count from 392 to 419 tests.

Jellyfin provides ratings through CommunityRating (typically TMDB,
0-10 scale) and CriticRating (typically Rotten Tomatoes, 0-100 scale
normalized to 0-10).

Map these to the existing rating rule properties:
- rating_imdb/rating_tmdb: Use CommunityRating (TMDB-sourced)
- rating_rottenTomatoesCritic: Use CriticRating
- rating_rottenTomatoesAudience: Use CommunityRating as approximation
- All *Show variants: Traverse to parent/grandparent for show metadata

This enables Jellyfin users to create rules based on ratings, which
previously returned null for all external rating properties.

Jellyfin genres don't have IDs, so we were using array index which was
fragile and could change between requests or items. Now using djb2 hash
algorithm to generate stable IDs from genre names.

Fixes review item #11.

During initial setup, the Plex and Jellyfin tabs were both visible
before the user selected a media server type. Now only the General
tab is shown until a selection is made.

Fixes review item #14.

…switch

Added a switchInProgress flag that:
- Prevents concurrent switch operations from starting
- Blocks factory.getService() calls during the switch
- Is always released in a finally block

This prevents API requests from routing to the wrong adapter during
the window between settings update and server initialization.

Fixes review item #8.

…apters

- Document error handling contract in IMediaServerService interface:
  - Read operations return empty/undefined on failure
  - Write operations throw with descriptive message
- Add try/catch with logging to Plex adapter write operations
- Improve error messages to include context (collection ID, item ID, etc.)

Fixes review item #10.

The lock added to MediaServerFactory caused a circular dependency
between MediaServerModule and SettingsModule. Removed the lock
entirely as it was over-engineering - the switch operation is
rare and short-lived.

- Hide Plex and Tautulli rules when on Jellyfin media server
- Hide Jellyfin rules when on Plex media server
- Use MediaServerType enum from contracts instead of string literals

- Replace string literals 'plex' and 'jellyfin' with MediaServerType enum
- Update Settings/index.tsx to use enum for tab visibility
- Update MediaServerSelector to use enum for all comparisons

Merge origin/main to bring in:
- Database download/backup functionality
- Apple touch icon for webapp
- 3.0 update banner removal
- Dependency bumps

Conflicts resolved by keeping both branches' changes:
- settings.controller.ts: both MediaServerSwitchService and DatabaseDownloadService
- settings.module.ts: combined providers/exports from both branches
- settings.ts (api): kept jellyfin hooks + downloadDatabase function
- Settings/Main/index.tsx: both MediaServerSelector and DatabaseBackupModal imports
- search-context.tsx: adopted main's stricter type annotation

Fixes from security review (H2, H4, M1, M7, L4):

H2 - Race condition on media server switch:
  Add mutex flag to executeSwitch() with 409 Conflict on concurrent calls.

H4 - API keys/tokens exposed in GET /settings:
  Mask secrets (first4...last4) in getPublicSettings(). Add dedicated
  GET /settings/jellyfin endpoint for real values. Move Plex token
  verification server-side for existing (masked) tokens.

M1 - No validation on SwitchMediaServerRequest:
  Add Zod schema (switchMediaServerSchema) with ZodValidationPipe.
  Also add ParseEnumPipe on switch preview path param.

M7 - State divergence during media server switch:
  MediaServerFactory.getService() checks isSwitching() and returns
  503 Service Unavailable during the switch window.

L4 - deleteFromDisk without safety checks:
  Validate itemId is non-empty (throw on empty instead of silent return).
  Add audit-level logging for destructive operations in both Jellyfin
  and Plex adapters. Throw on uninitialized Jellyfin API.

Additional cleanup:
  Remove dead AbortController code in Plex verifyToken.
  Export MediaServerSwitchService from SettingsModule.

…le usage

fix(jellyfin): remove double normalization of CriticRating (#2375)

improve loggning

Removed warning about development branch and Jellyfin support.