Add support for remote post serve action

[kapishmalik]

Incorporated following changes:

• Added support for remote post serve action
• Unit Tests
• Integration Tests
• Documentation

[tommysitu]

Looks great 👍, only one comment.

Also could we include the following in the next PR please?

• Log a message saying a (local/remote) post-serve-action is set, I think we have done the same for middleware.
• Update the Journal entry to indicate the request has triggered a callback, for example:

"response": {
        "status": 200,
        "body": "Hello World",
        "encodedBody": false,
        "headers": {
          "Content-Length": [
            "11"
          ]
        }
      },
"postServeAction": {
        "name": "outbound-http",
        "invoked": "2024-04-07T10:51:25.428+08:00",
        "completed": "2024-04-07T10:51:26.428+08:00",
        "correlationId": "1ce7ea0c-7b0d-4cc5-9f7c-4a406b0e3c48",
        "httpStatus": 200
 },

We need to include correlationId and httpStatus code for remote action only:
correlationId - a randomly generated UUID passed as X-CORRELATION-ID header to the remote action endpoint, user can use it for e2e tracing.
httpStatus - the response status code from the remote action endpoint.

Thanks!