API to count files associated with an APIKey

[rajat1saxena]

In the api project, create an endpoint to get total number of files associated with an API key.

Tech design:

1. In the apps/api/lib/media/routes.ts file, add the following route:

   POST /get/count

2. The above will call the handler getMediaCount which will be created in the file apps/api/lib/media/handlers.ts.

3. The getMediaCount method will get the total count of the files associated with the apikey and return it.

Expected response:

{count: 500}