fix(app): fix image fallbacks across all content grids, refactor into useContentImages

- Create useContentImages<T> composable eliminating ~240 lines of duplicated
  image loading/fallback logic across 6 grid components
- Fix book covers: use full fetchBookImage chain (Open Library → Google Books → Wikipedia)
- Fix TV series images: try disambiguated Wikipedia title first (e.g. "Chernobyl (TV series)")
- Add Wikipedia image fetching for places (fetchPlaceImage)
- Rewrite all SVG fallbacks to consistent text-only style (no icons)
- Add generateWebsiteFallback for NewsGrid websites variant
- Fix song extraction regex catching raw song_ext: prefix in titles
- Fix player bar: clean song_ext: prefix from display, mute error text
- Fix Code panel: auto-load projects on mount when list is empty
- Improve chat bubble spacing (py-2.5) and first message top margin (pt-6)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/app/src/composables/contentExtraction.ts

@@ -581,7 +581,8 @@ function extractSongsFromPatterns(text: string): Song[] {
       if (title.length < 2 || artist.length < 2) continue
       if (!looksLikeSong(title, artist)) continue
       if (/^\d{4}$/.test(title) || /^\d{4}$/.test(artist)) continue
-      if (/\[\[(film|song)(_ext)?:/.test(title) || /\[\[(film|song)(_ext)?:/.test(artist)) continue
+      if (/(\[\[)?(film|song|podcast|book|tv|place|recipe|event)(_ext)?:/i.test(title)) continue
+      if (/(\[\[)?(film|song|podcast|book|tv|place|recipe|event)(_ext)?:/i.test(artist)) continue
       if (/\*\*\[\[/.test(title) || title.includes(']]**')) continue
       const key = `${title.toLowerCase()}|${artist.toLowerCase()}`
       if (seen.has(key)) continue