Add actor/cast information with person pages and search support

Integrate TMDB credits data into the app: cast carousels on title detail
pages, person detail pages with biography and filmography, and person
search results in the command palette. Includes new persons/titleCast
DB tables, profile image caching, and a nightly credits refresh cron job.

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

lib/tmdb/image.ts

@@ -5,6 +5,7 @@ const IMAGE_BASE_URL =
 
 function sizeToCategory(size: string): ImageCategory {
   if (size === "w92") return "logos";
+  if (size === "w185") return "profiles";
   if (size === "w1280") return "backdrops";
   return "posters";
 }