fix: ensure proper datapoint decoding check in v1_protocol and update V1Channel connection strategy documentation

Author: allenporter

docs/DEVICES.md

@@ -357,7 +357,7 @@ graph LR
 1. **Temporary Subscriptions**: Each RPC creates a temporary subscription that matches the request ID
 2. **Subscription Reuse**: `MqttSession` keeps subscriptions alive for 60 seconds (or idle timeout) to enable reuse during command bursts
 3. **Timeout Handling**: Commands timeout after 10 seconds if no response is received
-4. **Multiple Strategies**: `V1Channel` tries local first, then falls back to MQTT if local fails
+4. **Multiple Strategies**: `V1Channel` tries connect to both Local faster local commands and MQTT for streaming updates.
 
 ## Class Design & Components
 

roborock/protocols/v1_protocol.py

@@ -235,7 +235,7 @@ def decode_data_protocol_message(message: RoborockMessage) -> dict[RoborockDataP
     Returns a dict mapping RoborockDataProtocol to values, or None if the
     message does not contain any recognized data protocol updates.
     """
-    if not (datapoints := _decode_dps_message(message)):
+    if (datapoints := _decode_dps_message(message)) is None:
         return None
 
     result: dict[RoborockDataProtocol, Any] = {}