Log mailbox refresh failures safely

src/govoplan_mail/backend/router.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import dataclasses
+import logging
 from types import SimpleNamespace
 from typing import Any
 
@@ -69,6 +70,7 @@ from govoplan_mail.backend.sending.imap import ImapAppendError, ImapConfiguratio
 from govoplan_mail.backend.sending.smtp import test_smtp_login
 
 router = APIRouter(prefix="/mail", tags=["mail"])
+logger = logging.getLogger(__name__)
 
 MAIL_MODULE_ID = "mail"
 MAIL_PROFILES_COLLECTION = "mail.profiles"
@@ -497,7 +499,12 @@ def _refresh_mailbox_index_task(
     except Exception:
         # Background refresh is opportunistic. Foreground requests will surface
         # concrete IMAP errors when no usable cache is available.
-        pass
+        logger.debug(
+            "Background mailbox index refresh failed (profile_id=%r, folder=%r)",
+            profile_id,
+            folder,
+            exc_info=True,
+        )
     finally:
         finish_mailbox_refresh(tenant_id, profile_id, folder)
 
@@ -826,7 +833,7 @@ def write_mail_profile_policy(
     scope_type = scope_type.strip().casefold()
     _require_policy_write_scope(principal, scope_type)
     try:
-        policy = set_mail_profile_policy(
+        set_mail_profile_policy(
             session,
             tenant_id=principal.tenant_id,
             scope_type=scope_type,