feat: show episode info on download and history cards

- Add includeEpisode:true to Sonarr queue and history API requests
  in both the poller and historyFetcher
- Add extractEpisode() / gatherEpisodes() helpers in dashboard.js
  and history.js to build a sorted, deduplicated episodes array
  covering all records matching a download title (handles multi-
  episode packs and series packs)
- Replace episodeInfo: sonarrMatch with episodes: gatherEpisodes()
  across all 8 assignment sites in dashboard.js
- Add episodes field to /api/history/recent response items
- Frontend: formatEpisodeInfo() renders S01E05 for single episodes
  or 'Multiple episodes' with hover tooltip listing all for packs
- CSS: .episode-info and .multi-episode tooltip styles
- ARCHITECTURE.md: update polling table and download/history schemas

server/utils/historyFetcher.js

@@ -35,6 +35,7 @@ async function fetchSonarrHistory(since) {
           sortKey: 'date',
           sortDir: 'descending',
           includeSeries: true,
+          includeEpisode: true,
           startDate: since.toISOString()
         }
       });