Fix: ignore system messages and own messages in router

System messages (task lifecycle) were being forwarded to agent as
new prompts, causing duplicate task creation. Agent also received
its own chat.send broadcasts back and processed them.

src/router.ts

@@ -79,6 +79,18 @@ export class EventRouter {
       return;
     }
 
+    // Ignore system messages — they are lifecycle notifications, not user input
+    if (authorType === 'system') {
+      this.log.info('│  Skipping system message: "%s"', content.slice(0, 100));
+      return;
+    }
+
+    // Ignore own messages (agent talking to itself)
+    if (resolvedAuthorSlug === this.config.slug) {
+      this.log.info('│  Skipping own message');
+      return;
+    }
+
     // Build context-rich prompt for the agent
     const ctx = taskId ? `[задача ${taskKey || taskId}]` : chatId ? '[чат]' : '';
     const from = authorType === 'system' ? '[система]' : `@${resolvedAuthorSlug}`;