Implement credit parse result polling and sentinel handling

lsfx-mock-server/routers/credit_api.py

@@ -12,6 +12,7 @@ router = APIRouter()
 payload_service = CreditPayloadService("config/credit_feature_schema.json")
 debug_service = CreditDebugService("config/credit_response_examples.json")
 identity_service = CreditHtmlIdentityService()
+result_cache = {}
 
 
 @router.post("/api/service/interface/invokeService/xfeature")
@@ -40,6 +41,27 @@ async def html_eval(
         filename=remote_filename(remotePath),
         subject_identity=subject_identity,
     )
+    result_cache[serialNum] = payload
+    return debug_service.build_initiate_success_response(serialNum)
+
+
+@router.post("/api/service/interface/invokeService/xfeatureResult")
+async def html_eval_result(
+    serialNum: Optional[str] = Form(None),
+    orgCode: Optional[str] = Form(None),
+    runType: Optional[str] = Form(None),
+):
+    error_response = debug_service.validate_result_request(
+        serial_num=serialNum,
+        org_code=orgCode,
+        run_type=runType,
+    )
+    if error_response:
+        return error_response
+
+    payload = result_cache.get(serialNum)
+    if payload is None:
+        return debug_service.build_result_not_found_response(serialNum)
     return debug_service.build_success_response(payload)