test: align QuotaInsufficientError fixtures with balance_micros API

Billable calls now raise quota errors with balance_micros instead of
used_micros/limit_micros; update mocks so CI passes on main.

surfsense_backend/tests/integration/podcasts/test_draft_task.py

@@ -76,8 +76,7 @@ async def test_quota_denial_fails_the_podcast_without_a_transcript(
     async def _deny(**_kwargs):
         raise QuotaInsufficientError(
             usage_type="podcast_generation",
-            used_micros=5_000_000,
-            limit_micros=5_000_000,
+            balance_micros=5_000_000,
             remaining_micros=0,
         )
         yield  # pragma: no cover - unreachable, satisfies the CM protocol

surfsense_backend/tests/unit/services/test_quota_checked_vision_llm.py

@@ -105,8 +105,7 @@ async def test_ainvoke_propagates_quota_insufficient_error(monkeypatch):
     async def _denying_billable_call(**_kwargs):
         raise QuotaInsufficientError(
             usage_type="vision_extraction",
-            used_micros=5_000_000,
-            limit_micros=5_000_000,
+            balance_micros=5_000_000,
             remaining_micros=0,
         )
         yield  # unreachable but required for asynccontextmanager type

surfsense_backend/tests/unit/tasks/test_video_presentation_billing.py

@@ -98,8 +98,7 @@ async def _denying_billable_call(**kwargs):
     _CALL_LOG.append(kwargs)
     raise QuotaInsufficientError(
         usage_type=kwargs.get("usage_type", "?"),
-        used_micros=5_000_000,
-        limit_micros=5_000_000,
+        balance_micros=5_000_000,
         remaining_micros=0,
     )
     yield SimpleNamespace()  # pragma: no cover