fix(gateway/bluebubbles): fall back to data.chats[0].guid when chatGuid missing

BlueBubbles v1.9+ webhook payloads for new-message events do not always
include a top-level chatGuid field on the message data object. Instead,
the chat GUID is nested under data.chats[0].guid.

The adapter currently checks five top-level fallback locations (record and
payload, snake_case and camelCase, plus payload.guid) but never looks
inside the chats array. When none of those top-level fields contain the
GUID, the adapter falls through to using the sender's phone/email as the
session chat ID.

This causes two observable bugs when a user is a participant in both a DM
and a group chat with the bot:

1. DM and group sessions merge. Every message from that user ends up with
   the same session_chat_id (their own address), so the bot cannot
   distinguish which thread the message came from.

2. Outbound routing becomes ambiguous. _resolve_chat_guid() iterates all
   chats and returns the first one where the address appears as a
   participant; group chats typically sort ahead of DMs by activity, so
   replies and cron messages intended for the DM can land in a group.

This was observed in production: a user's morning brief cron delivered to
a group chat with his spouse instead of his DM thread.

The fix adds a single fallback that extracts chat_guid from
record["chats"][0]["guid"] when the top-level fields are empty. The chats
array is included in every new-message webhook payload in BB v1.9.9
(verified against a live server). It is backwards compatible: if a future
BB version starts including chatGuid at the top level, that still wins.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

gateway/platforms/bluebubbles.py

@@ -835,6 +835,12 @@ class BlueBubblesAdapter(BasePlatformAdapter):
             payload.get("chat_guid"),
             payload.get("guid"),
         )
+        # Fallback: BlueBubbles v1.9+ webhook payloads omit top-level chatGuid;
+        # the chat GUID is nested under data.chats[0].guid instead.
+        if not chat_guid:
+            _chats = record.get("chats") or []
+            if _chats and isinstance(_chats[0], dict):
+                chat_guid = _chats[0].get("guid") or _chats[0].get("chatGuid")
         chat_identifier = self._value(
             record.get("chatIdentifier"),
             record.get("identifier"),

tests/gateway/test_bluebubbles.py

@@ -167,6 +167,63 @@ class TestBlueBubblesWebhookParsing:
             chat_identifier = sender
         assert chat_identifier == "user@example.com"
 
+    def test_webhook_extracts_chat_guid_from_chats_array_dm(self, monkeypatch):
+        """BB v1.9+ webhook payloads omit top-level chatGuid; GUID is in chats[0].guid."""
+        adapter = _make_adapter(monkeypatch)
+        payload = {
+            "type": "new-message",
+            "data": {
+                "guid": "MESSAGE-GUID",
+                "text": "hello",
+                "handle": {"address": "+15551234567"},
+                "isFromMe": False,
+                "chats": [
+                    {"guid": "any;-;+15551234567", "chatIdentifier": "+15551234567"}
+                ],
+            },
+        }
+        record = adapter._extract_payload_record(payload) or {}
+        chat_guid = adapter._value(
+            record.get("chatGuid"),
+            payload.get("chatGuid"),
+            record.get("chat_guid"),
+            payload.get("chat_guid"),
+            payload.get("guid"),
+        )
+        if not chat_guid:
+            _chats = record.get("chats") or []
+            if _chats and isinstance(_chats[0], dict):
+                chat_guid = _chats[0].get("guid") or _chats[0].get("chatGuid")
+        assert chat_guid == "any;-;+15551234567"
+
+    def test_webhook_extracts_chat_guid_from_chats_array_group(self, monkeypatch):
+        """Group chat GUIDs contain ;+; and must be extracted from chats array."""
+        adapter = _make_adapter(monkeypatch)
+        payload = {
+            "type": "new-message",
+            "data": {
+                "guid": "MESSAGE-GUID",
+                "text": "hello everyone",
+                "handle": {"address": "+15551234567"},
+                "isFromMe": False,
+                "isGroup": True,
+                "chats": [{"guid": "any;+;chat-uuid-abc123"}],
+            },
+        }
+        record = adapter._extract_payload_record(payload) or {}
+        chat_guid = adapter._value(
+            record.get("chatGuid"),
+            payload.get("chatGuid"),
+            record.get("chat_guid"),
+            payload.get("chat_guid"),
+            payload.get("guid"),
+        )
+        if not chat_guid:
+            _chats = record.get("chats") or []
+            if _chats and isinstance(_chats[0], dict):
+                chat_guid = _chats[0].get("guid") or _chats[0].get("chatGuid")
+        assert chat_guid == "any;+;chat-uuid-abc123"
+
     def test_extract_payload_record_accepts_list_data(self, monkeypatch):
         adapter = _make_adapter(monkeypatch)
         payload = {