API gateway with mock capability

Is your feature request related to a problem? Please describe.
Needed a mock service based on proxy capability. The required mock service must be able to intercept incoming requests and return mock response if configured or forwards to existing live service.

Describe the solution you'd like
I have developed a framework on top of Spring Cloud Gateway to enable mock configuration based on properties/config service. This framework allows to add mock configuration for a given API endpoint. This mock API either produces mock response
or proxies the requests to live the service. The mock can be turned on/off for a given endpoint. It can also help to simulate difficult cases like timeouts for outbound calls by adding delays to mock response. Also, the mock configuration is property based which doesn’t require any modification.

Describe alternatives you've considered
There are few json-server which can be quickly configured and started. But it does not have a proxy capability.

Additional context

No files, tests, or entry points are named. Start by reviewing the existing Spring Cloud Gateway routing and proxy behavior, then clarify the configuration model, endpoint interception, mock-versus-live forwarding, enable/disable behavior, and delayed responses before implementation.