Format code with Prettier (8 modified files from H1 decomposition)

Aligns with CC2 enforcement: ESLint + Prettier + noImplicitAny now enforced.

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

src/main/sources.ts

@@ -16,11 +16,11 @@ import type { Source, MediaItem } from '@shared/ipc'
 import { isValidSource, isValidMediaItem } from './validation'
 import { mergeItemsPreservingState } from './indexerCore'
 import { createJsonStore } from './jsonStore'
-
-// A generous global cap so a runaway index can't grow the file unbounded; large
-// enough for several big channels. When exceeded, the most-recently-written
-// source's items are kept (they're placed first by replaceMediaItems).
-const MAX_ITEMS = 20000
+// A generous global cap (MEDIA_ITEMS_MAX, see constants.ts) so a runaway index
+// can't grow the file unbounded; large enough for several big channels. When
+// exceeded, the most-recently-written source's items are kept (they're placed
+// first by replaceMediaItems).
+import { MEDIA_ITEMS_MAX as MAX_ITEMS } from './constants'
 
 // Two cached, atomically-written stores (R1–R3 via the shared jsonStore). The
 // media-items store is the hot path: setMediaItemDownloaded used to re-read and