fix search/filter bugs in game and TV libraries

- Game series: filter now checks child games for both search and tag matches instead of always passing series through
- TV episodes: tag selector no longer closes after picking a tag
- TV episodes: filter panel now filters episodes within a season view
- TV series list: series now appear when any of their episodes match the active tag filter (via new /api/tv/series-episode-tags endpoint backed by media_items)

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

src/components/games/GamesView.tsx

@@ -74,10 +74,21 @@ export default function GamesView({ libraryId }: Props) {
     : items
 
   const filtered = visibleItems.filter((item) => {
+    if ('games' in item) {
+      const searchMatch = !search ||
+        item.title.toLowerCase().includes(search.toLowerCase()) ||
+        item.games.some((g) => g.title.toLowerCase().includes(search.toLowerCase()))
+      if (!searchMatch) return false
+      if (selectedTagIds.size > 0) {
+        return item.games.some((g) => {
+          const gameTags = assignments[`${libraryId}:${g.id}`] ?? []
+          return [...selectedTagIds].every((id) => gameTags.includes(id))
+        })
+      }
+      return true
+    }
     if (search && !item.title.toLowerCase().includes(search.toLowerCase())) return false
     if (selectedTagIds.size > 0) {
-      // Tag filtering only applies to games (series don't have tags directly)
-      if ('games' in item) return true
       const gameTags = assignments[`${libraryId}:${item.id}`] ?? []
       if (![...selectedTagIds].every((id) => gameTags.includes(id))) return false
     }