Feat/health check api endpoint

[gitit24x7]

I've added a simple Health Check endpoint at /api/health.

This is super useful for setting up uptime monitors (like UptimeRobot or Railway) to make sure our backend is alive and kicking. The response is lightweight and runs on the edge, so it's really fast and won't slow anything down.

You can test it here:
GET /api/health

It returns a JSON object like this:

{
  "status": "ok",
  "version": "0.1.0",
  "uptime": 123.45
}

closes #406 

[gitit24x7]

@Sree14hari Can you please check and approve too if all ok?

[Sree14hari]

@gitit24x7 it have merge conflicts

[gitit24x7]

@Sree14hari conflicts resolved. Please check now

[Sree14hari]

@gitit24x7 conflicts