Address claude-review round 3 on #922:
- Important: _process_batch emitted "no gateway backend (provider=mistral or
EMBEDDING_GATEWAY_URL unset)" for the gateway_only in-cluster rung, where the
gateway IS configured — sending operators chasing a non-existent config
problem. The real reason is "in-cluster GPU is synchronous-only; batch is the
upstream path". Guard the warning with `if not self._gateway_only`. Extended
test_gateway_only_processor_never_uses_batch_mode to drive _process_batch and
assert _batch_fallback_warned stays False.
- Nits: refresh stale ladder in escalation.py module docstring
(fast->structured->ocr-incluster->ocr-upstream); fix "minimum='ocr'" ->
"ocr-incluster" in a test docstring; rename stale tier="ocr" ->
"ocr-upstream" in test_process_tier_oversize_fails_fast.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
