fix: log omitted OpenRouter request manifests

Co-authored-by: Copilot App <[email protected]>

tests/providers/test_openrouter.py

@@ -1,6 +1,7 @@
 """Tests for transcription.providers.openrouter."""
 
 import asyncio
+import logging
 from types import SimpleNamespace
 from typing import cast
 
@@ -226,3 +227,21 @@ class TestOpenRouterProviderTranscribe:
         assert result.text == "Transcript text"
         assert result.metadata_payload() is None
         assert result.raw_api_response == response
+
+    @pytest.mark.asyncio
+    async def test_logs_when_request_manifest_is_omitted_without_source_reference(self, caplog):
+        response = {"model": "vendor/model-a", "choices": [{"message": {"content": "Transcript text"}}]}
+        provider = OpenRouterTranscriptionProvider(
+            settings=Settings(openrouter_api_key="test-key"),
+            client=_fake_client(response=response),
+        )
+
+        with caplog.at_level(logging.WARNING):
+            result = await provider.transcribe(
+                prompt_text="Prompt body",
+                image_bytes=b"img-bytes",
+                mime_type="image/png",
+            )
+
+        assert result.request_manifest is None
+        assert "request manifest omitted" in caplog.text.lower()