Reset now clears emails and comments as well as answers

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

app.py

@@ -1432,6 +1432,10 @@ def reset():
     _session_version[0] += 1  # invalidates all existing phone sessions
     _stream_state['running'] = False
     _stream_state['progress'] = 0
+    with open(COMMENTS_FILE, 'w') as f:
+        json.dump([], f)
+    with open(EMAILS_FILE, 'w') as f:
+        json.dump([], f)
     return jsonify({'ok': True})