fix(ucs): cybersource psync shadow mode returns false CONNECTOR_ERROR_RESPONSE for disabled connectors

[AmitsinghTanwar007]

Root cause

When a connector is in ucs_psync_disabled_connectors, the psync gateway returns early in shadow mode without making the UCS gRPC call. This causes the comparison service to see a router_data with:

• connector_http_status_code = null (never set because no API call was made)
• response.Err.code = "CONNECTOR_ERROR_RESPONSE" (placeholder from an uninitialized error path)

While HS returns real values from the connector API call:

• connector_http_status_code = <number>
• response.Err.code = "No error code"

Diffs observed

• router.valueDiff:response.Err.code
• router.typeDiff:connector_http_status_code

Fix

Gate the early-return on ExecutionMode != Shadow so UCS always makes the API call in shadow mode.

See PR #13085.