Check API health

Example response

{
  "posthog": {
    "api_key_configured": true,
    "enabled": true,
    "host": "https://us.i.posthog.com",
    "initialized": true,
    "status": "ok"
  },
  "redis": {
    "connected": true,
    "connection_info": {
      "available_connections": 18,
      "max_connections": 20
    },
    "status": "ok"
  },
  "status": "healthy",
  "version": "1.0.0",
  "weaviate": {
    "status": "connected",
    "version": "1.23.0"
  }
}