Implement a Proxy server in FDK for testing serverless apps

When developing apps that require a serverless backend, the current local test environment Serverless App Testing is not very helpful because the data used to simulate an event is hardcoded and does not have any dynamic values, even for dates. Modifying and verifying hundreds of lines of JSON data by hand just to test simple functionalities degrades the developer experience.

This means that we have to create a new custom app to mimic expected app behavior, and this makes the development or debugging process very tedious. as We may have to change and update the custom app every time we modify something, which affects the developer experience negatively.

To solve this problem, I suggest adding a proxy server in the CLI for testing and debugging. For an example, see Netlify CMS Proxy Server (Now Decap CMS) or provide a docker image that replicates the Freshworks backend infrastructure. In both instances we would have something running in our local environment mimicing production environment similar to most other Developer platforms that offers serverless functions.

Thanks for this feedback @falconZ.

@Archana_Sreekantaswa for visibility.