feat(db): add EPG schema and IPC handlers for EPG storage

Add tables, indexes, FTS5 virtual table, and triggers to support EPG
(electronic program guide) data in the shared SQLite connection. The
changes introduce epg_channels and epg_programs tables, multiple
indexes for efficient lookups (by source, name, channel, start, and
time range), and an epg_programs_fts virtual table with triggers to
keep the full-text index synchronized with epg_programs.

Register EPG database event handlers in the Electron backend and
add an IPC handler for bulk-saving channels. The handler deletes
existing channels for a source and inserts new channels in chunks to
avoid large single inserts, returning the inserted count.

These changes enable storing, querying, and full-text searching EPG
data and prepare backend IPC endpoints for importing program guide
data.

libs/shared/database/src/lib/connection.ts

@@ -105,6 +105,57 @@ const CREATE_TABLE_STATEMENTS = [
   `CREATE UNIQUE INDEX IF NOT EXISTS recently_viewed_content_playlist_unique ON recently_viewed(content_id, playlist_id)`,
   `CREATE INDEX IF NOT EXISTS recently_viewed_playlist_idx ON recently_viewed(playlist_id)`,
   `CREATE INDEX IF NOT EXISTS recently_viewed_viewed_at_idx ON recently_viewed(viewed_at)`,
+  // EPG tables
+  `CREATE TABLE IF NOT EXISTS epg_channels (
+      id TEXT PRIMARY KEY,
+      display_name TEXT NOT NULL,
+      icon_url TEXT,
+      url TEXT,
+      source_url TEXT NOT NULL,
+      updated_at TEXT DEFAULT (datetime('now'))
+  )`,
+  `CREATE TABLE IF NOT EXISTS epg_programs (
+      id INTEGER PRIMARY KEY AUTOINCREMENT,
+      channel_id TEXT NOT NULL,
+      start TEXT NOT NULL,
+      stop TEXT NOT NULL,
+      title TEXT NOT NULL,
+      description TEXT,
+      category TEXT,
+      icon_url TEXT,
+      rating TEXT,
+      episode_num TEXT,
+      FOREIGN KEY (channel_id) REFERENCES epg_channels(id) ON DELETE CASCADE
+  )`,
+  // EPG indexes
+  `CREATE INDEX IF NOT EXISTS idx_epg_channels_source ON epg_channels(source_url)`,
+  `CREATE INDEX IF NOT EXISTS idx_epg_channels_name ON epg_channels(display_name)`,
+  `CREATE INDEX IF NOT EXISTS idx_epg_programs_channel ON epg_programs(channel_id)`,
+  `CREATE INDEX IF NOT EXISTS idx_epg_programs_start ON epg_programs(start)`,
+  `CREATE INDEX IF NOT EXISTS idx_epg_programs_time_range ON epg_programs(channel_id, start, stop)`,
+  // FTS5 virtual table for full-text search on EPG programs
+  `CREATE VIRTUAL TABLE IF NOT EXISTS epg_programs_fts USING fts5(
+      title,
+      description,
+      category,
+      content='epg_programs',
+      content_rowid='id'
+  )`,
+  // Triggers to keep FTS index in sync with epg_programs table
+  `CREATE TRIGGER IF NOT EXISTS epg_programs_ai AFTER INSERT ON epg_programs BEGIN
+      INSERT INTO epg_programs_fts(rowid, title, description, category)
+      VALUES (new.id, new.title, new.description, new.category);
+  END`,
+  `CREATE TRIGGER IF NOT EXISTS epg_programs_ad AFTER DELETE ON epg_programs BEGIN
+      INSERT INTO epg_programs_fts(epg_programs_fts, rowid, title, description, category)
+      VALUES ('delete', old.id, old.title, old.description, old.category);
+  END`,
+  `CREATE TRIGGER IF NOT EXISTS epg_programs_au AFTER UPDATE ON epg_programs BEGIN
+      INSERT INTO epg_programs_fts(epg_programs_fts, rowid, title, description, category)
+      VALUES ('delete', old.id, old.title, old.description, old.category);
+      INSERT INTO epg_programs_fts(rowid, title, description, category)
+      VALUES (new.id, new.title, new.description, new.category);
+  END`,
 ];
 
 /**

libs/shared/database/src/lib/schema.ts

@@ -123,6 +123,51 @@ export const favorites = sqliteTable(
     })
 );
 
+// EPG Channels table
+export const epgChannels = sqliteTable(
+    'epg_channels',
+    {
+        id: text('id').primaryKey(), // Channel ID from EPG source
+        displayName: text('display_name').notNull(),
+        iconUrl: text('icon_url'),
+        url: text('url'),
+        sourceUrl: text('source_url').notNull(), // Which EPG URL this came from
+        updatedAt: text('updated_at').default(sql`CURRENT_TIMESTAMP`),
+    },
+    (table) => ({
+        sourceIdx: index('idx_epg_channels_source').on(table.sourceUrl),
+        nameIdx: index('idx_epg_channels_name').on(table.displayName),
+    })
+);
+
+// EPG Programs table
+export const epgPrograms = sqliteTable(
+    'epg_programs',
+    {
+        id: integer('id').primaryKey({ autoIncrement: true }),
+        channelId: text('channel_id')
+            .notNull()
+            .references(() => epgChannels.id, { onDelete: 'cascade' }),
+        start: text('start').notNull(), // ISO datetime
+        stop: text('stop').notNull(), // ISO datetime
+        title: text('title').notNull(),
+        description: text('description'),
+        category: text('category'),
+        iconUrl: text('icon_url'),
+        rating: text('rating'),
+        episodeNum: text('episode_num'),
+    },
+    (table) => ({
+        channelIdx: index('idx_epg_programs_channel').on(table.channelId),
+        startIdx: index('idx_epg_programs_start').on(table.start),
+        timeRangeIdx: index('idx_epg_programs_time_range').on(
+            table.channelId,
+            table.start,
+            table.stop
+        ),
+    })
+);
+
 // Type exports for TypeScript
 export type Playlist = typeof playlists.$inferSelect;
 export type NewPlaylist = typeof playlists.$inferInsert;
@@ -138,3 +183,9 @@ export type NewRecentlyViewed = typeof recentlyViewed.$inferInsert;
 
 export type Favorite = typeof favorites.$inferSelect;
 export type NewFavorite = typeof favorites.$inferInsert;
+
+export type EpgChannel = typeof epgChannels.$inferSelect;
+export type NewEpgChannel = typeof epgChannels.$inferInsert;
+
+export type EpgProgramDb = typeof epgPrograms.$inferSelect;
+export type NewEpgProgramDb = typeof epgPrograms.$inferInsert;