Add queue handler and tag-based queue dispatcher

- Add queue() handler in index.ts for WORK_QUEUE processing
- Add consumers/queue-dispatcher.ts with tag-based routing

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

src/index.ts

@@ -114,6 +114,24 @@ app.notFound((c) => c.text('Not Found', 404));
 export default {
   fetch: app.fetch,
 
+  async queue(batch: MessageBatch, env: Env): Promise<void> {
+    const { dispatchQueueMessage } = await import('./consumers/queue-dispatcher');
+    const queueLogger = createLogger('queue');
+
+    for (const msg of batch.messages) {
+      try {
+        await dispatchQueueMessage(msg.body, env);
+        msg.ack();
+      } catch (error) {
+        queueLogger.error('Queue message processing failed', error as Error, {
+          queue: batch.queue,
+          messageId: msg.id,
+        });
+        msg.retry();
+      }
+    }
+  },
+
   async scheduled(event: ScheduledEvent, env: Env, _ctx: ExecutionContext): Promise<void> {
     const cronSchedule = event.cron;
     logger.info('Cron job started', { schedule: cronSchedule });