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

public/app.js

@@ -290,6 +290,30 @@ function hideLoginError() {
   errorDiv.style.display = 'none';
 }
 
+// Build an episode-info element for series downloads/history.
+// Single episode: "S01E05 — Episode Title"
+// Multiple episodes: "Multiple episodes" with tooltip listing them all.
+// Returns null if no episode data.
+function formatEpisodeInfo(episodes) {
+  if (!episodes || episodes.length === 0) return null;
+  const el = document.createElement('p');
+  el.className = 'episode-info';
+  if (episodes.length === 1) {
+    const ep = episodes[0];
+    const code = 'S' + String(ep.season).padStart(2, '0') + 'E' + String(ep.episode).padStart(2, '0');
+    el.textContent = ep.title ? code + ' \u2014 ' + ep.title : code;
+  } else {
+    el.textContent = 'Multiple episodes';
+    el.classList.add('multi-episode');
+    const lines = episodes.map(ep => {
+      const code = 'S' + String(ep.season).padStart(2, '0') + 'E' + String(ep.episode).padStart(2, '0');
+      return ep.title ? code + ' \u2014 ' + ep.title : code;
+    });
+    el.setAttribute('data-tooltip', lines.join('\n'));
+  }
+  return el;
+}
+
 // fetchUserDownloads is kept for the showAll toggle re-connection case
 // but the primary data path is now via SSE (startSSE / EventSource).
 
@@ -478,6 +502,8 @@ function createDownloadCard(download) {
       series.textContent = `Series: ${download.seriesName}`;
     }
     infoDiv.appendChild(series);
+    const epEl = formatEpisodeInfo(download.episodes);
+    if (epEl) infoDiv.appendChild(epEl);
   }
   
   if (download.movieName) {
@@ -982,6 +1008,8 @@ function createHistoryCard(item) {
       p.textContent = 'Series: ' + item.seriesName;
     }
     info.appendChild(p);
+    const epEl = formatEpisodeInfo(item.episodes);
+    if (epEl) info.appendChild(epEl);
   }
   if (item.movieName) {
     const p = document.createElement('p');