Add metrics and refactor healthcheck

src/core/app.py

@@ -2,6 +2,7 @@ from fastapi import FastAPI
 
 import aioredis
 from fastapi_pagination import add_pagination
+from prometheus_fastapi_instrumentator import Instrumentator
 
 from app.views import users_router, languages_router, healthcheck_router
 from core.config import env_config
@@ -38,4 +39,6 @@ def start_app() -> FastAPI:
         if database_.is_connected:
             await database_.disconnect()
 
+    Instrumentator().instrument(app).expose(app, include_in_schema=True)
+
     return app