fix: force JSON output for Ollama intent classification; fix attachment detection

- ollama_backend: add format='json' for 'master' and receipt_parser
  callers so llama3.1:8b returns valid JSON instead of plain English
- ab_ai_mail: add debug logging to trace attachment_ids from Discuss;
  handle file-only messages and clarification look-back flow

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

addons/activeblue_ai/models/ab_ai_mail.py

@@ -84,6 +84,20 @@ class DiscussChannel(models.Model):
             return result
 
         text = _strip_html(body)
+
+        # Odoo 18 Discuss uploads attachments before posting the message and
+        # passes their IDs in kwargs as attachment_ids (list of ints or ORM
+        # commands).  result.attachment_ids resolves those after super() runs.
+        # Log both so we can see exactly what arrives.
+        _logger.info(
+            'AB AI mail hook: body=%r kwargs_keys=%s '
+            'attachment_ids_kwarg=%r result.attachment_ids=%s',
+            (body or '')[:80],
+            list(kwargs.keys()),
+            kwargs.get('attachment_ids'),
+            result.attachment_ids.ids,
+        )
+
         attachments = result.attachment_ids
 
         # Nothing to work with

agent_service/llm/ollama_backend.py

@@ -24,6 +24,11 @@ class OllamaBackend:
                 kwargs = {'model': self._model, 'messages': messages}
                 if tools:
                     kwargs['tools'] = tools
+                # Force structured JSON output for callers that parse JSON responses.
+                # Without this llama3.1:8b returns plain English instead of JSON.
+                _JSON_CALLERS = {'master', 'expenses_agent_receipt_parser'}
+                if caller in _JSON_CALLERS and not tools:
+                    kwargs['format'] = 'json'
                 client = ollama.AsyncClient(host=self._url)
                 try:
                     response = await asyncio.wait_for(client.chat(**kwargs), timeout=self._timeout)