The gateway already stored a created timestamp per channel/thread but never sent it over the wire. Now: - protocol.py: _channel_payload() includes created (unix seconds) - Protocol.kt: ChannelInfo.created (default 0.0 for legacy gateways) - ChatScreen: topic switcher sorts threads created-desc (newest right after General, swipe new -> old), name as tie-break - frames.schema.json: document the created field - ChannelCreatedWireTest: wire deserialization + ordering tests