Complete activity-core LLM endpoint handoff (LLM-WP-0006)

Switch the custodian triage default from anthropic/claude-sonnet-4 to
google/gemini-2.5-flash, which advertises structured-output support on
OpenRouter. Tighten the OpenRouter adapter to send strict JSON schema
requests and set provider.require_parameters=true so routing only hits
providers that honor the requested response_format.

Update Kubernetes deploy docs and config for the verified coulombcore
handoff: Containerfile build path, image-pull-policy=Never for smoke
pods, credential-routing notes, and live smoke evidence. Mark
LLM-WP-0006 finished with closure notes from 2026-06-18.

tests/test_payload.py

@@ -34,7 +34,7 @@ def test_openai_chat_model_params_translate_activity_core_shape():
         "json_schema": {
             "name": "structured_output",
             "schema": STRUCTURED_SCHEMA,
-            "strict": False,
+            "strict": True,
         },
     }
     assert payload["top_p"] == 0.8