袁聪的第三次提交，API接口完善

app/worker/runtime.py

@@ -10,7 +10,7 @@ from uuid import uuid4
 from sqlalchemy import select, update
 
 from app.core.config import Settings, get_settings
-from app.core.contracts import AgentRequest, AgentResult, RequestContext
+from app.core.contracts import AgentRequest, AgentRequestMetadata, AgentResult, RequestContext
 from app.core.errors import AgentError, RecoverableAgentError, RunLeaseLostError
 from app.infrastructure.db import SessionFactory
 from app.model.audit import InteractionAudit
@@ -425,7 +425,9 @@ class WorkerRuntime:
             request = AgentRequest(
                 agent_type=run.agent_type, message=message.content, session_id=run.session_id,
                 idempotency_key=idem.idempotency_key,
-                metadata=event.payload.get("metadata", {}) if event else {},
+                metadata=AgentRequestMetadata.model_validate(
+                    event.payload.get("metadata", {}) if event else {}
+                ),
             )
             identity = RequestContext(user_id=str(run.user_id), trace_id=run.trace_id)
         # Re-check account and permissions at execution time, including delayed jobs.