feat(search): add backend-scoped global search

[hotzenplotz5]

Summary

• Adds a backend-scoped global search for Recordings 2 and persisted EPG data.
• Searches titles, subtitles and normalized persisted people.
• Adds a mobile live-search launcher directly after the VDR remote entry.
• Reuses the existing Recordings 2 and EPG detail owners and retains query, result and scroll state.

Architecture

Frontend
  -> VdrSuiteClientApi
  -> GET /api/search
  -> GlobalSearchApiRuntime
  -> GlobalSearchController
  -> GlobalSearchService
  -> GlobalSearchRepository
  -> existing VDR-Suite SQLite database

Normal search GETs use the existing database through a dedicated PRAGMA query_only=ON connection. The browser never calls TVScraper, TMDB, IMDb, RESTfulAPI, SVDRP or SuiteBridge, and search performs no provider resolution.

Search performance hardening

The initial mobile test exposed a real latency problem with 174,164 persisted EPG events. The former query evaluated provider JSON and correlated person subqueries for each event and repeated the scan for count and result selection.

The final implementation now:

• produces title and person candidates in separate set-based query branches;
• merges candidates deterministically by backend/channel/event identity;
• parses no provider JSON during a normal search GET;
• performs person matching once over the normalized relation instead of per EPG row;
• returns total count and the page from one statement;
• retains the backend and EPG time-window bounds;
• adds a 12-second mobile request timeout so a pathological request shows an understandable error rather than spinning forever.

A regression fixture searches 174,164 synthetic EPG events for both Pulp Fiction and John Travolta and enforces a bounded runtime. Local measurements were approximately 0.1 seconds for those targeted searches and below 0.8 seconds for a deliberately broad two-character query.

API

GET /api/search?backend=<id>&query=<text>&limit=<n>&offset=<n>&from=<epoch>&until=<epoch>

• minimum query length: 2 folded characters
• default limit: 20 per group; maximum: 50
• default EPG window: now minus 6 hours through now plus 14 days
• maximum explicit EPG window: 31 days
• deterministic sorting and independent recording/EPG totals and hasMore
• unknown or disabled backends are rejected before repository access

Frontend

• 280 ms debounce
• AbortController, request-generation guard and 12-second timeout
• visible empty, too-short, loading, timeout/error and no-result states
• grouped Aufnahmen, EPG and optional person summaries
• Recordings 2 cards and existing Recordings 2 detail owner
• existing EPG detail owner
• responsive smartphone dialog and scroll behavior

The VDR remote and EPG timeline are unchanged. The old recording browser is not used.

PR #101 assessment

The conflicting old patch was not copied. Current main already has the consistent 128-person / 65,535-byte contract and its regression model keeps all 52 Pulp Fiction people, including John Travolta beyond the former 12-person cutoff. A future increase must update plugin, transport, backend parser and tests together.

Validation

Passed locally and in the publishing workflow:

• make test-global-search
• 174,164-event performance regression
• frontend stale-response and timeout tests
• architecture contract checks
• make test-docs
• git diff --check

Previously completed targeted validation also covers API routing, HTTP/install staging, Recordings 2, genre frontend, VDR remote, EPG timeline and daemon compilation paths. GitHub Actions is triggered again on the final one-commit branch.