Add Health Check Endpoint

[Akshola00]

initialize axum Add Health Check Endpoint

Description:
Create a /health route to verify the server status.

✅ Acceptance Criteria:

GET /health returns { "status": "ok" } JSON

[lucifer1017]

As an experienced Full Stack Web3 Developer, I can safely say, I can solve all of your Issues in under 2 days.

[bernardev254]

Hello am Bernard a rust backend dev and am confident to handle this issue.

I'll add a minimal /health endpoint in Axum with:

1. GET /health → { "status": "ok" } (JSON)
2. Zero dependencies
3. Proper routing integration