feat(moderation): enhance message capture and storage with thread support

- Added functions to retrieve message location, sticker metadata, and display content in messageCapture.ts.
- Updated captureMessage function to store thread information and sticker metadata in the database.
- Modified messageStore.ts to support querying messages and attachments by thread ID.
- Updated types.ts to include thread_id in AttachmentRecord.
- Altered database schema in muxer-queue.ts to add thread_id column to attachments.
- Introduced ChannelSummary interface and listWatchableChannels method in voiceController.ts to fetch watchable channels.
- Added API endpoint in webserver.ts to retrieve channels for a given guild.

src/muxer-queue.ts

@@ -84,6 +84,7 @@ function initializeDatabase(): SqliteDatabase {
       message_id TEXT NOT NULL,
       guild_id TEXT NOT NULL,
       channel_id TEXT NOT NULL,
+      thread_id TEXT,
       user_id TEXT NOT NULL,
       filename TEXT NOT NULL,
       size INTEGER NOT NULL,
@@ -102,6 +103,12 @@ function initializeDatabase(): SqliteDatabase {
     CREATE INDEX IF NOT EXISTS idx_attachments_status ON attachments(upload_status);
   `);
 
+  try {
+    database.exec("ALTER TABLE attachments ADD COLUMN thread_id TEXT");
+  } catch {
+    // Column already exists on databases initialized after the moderation schema was added.
+  }
+
   return database;
 }