add grafana loki promtail for monitoring

modules/nixos/monitoring/grafana.nix

@@ -0,0 +1,46 @@
+{
+  lib,
+  username,
+  ...
+}: {
+  services = {
+    grafana = {
+      enable = true;
+      settings = {
+        server.http_port = 8888;
+        security = {
+          admin_user = "${username}";
+          admin_email = "0xtux@pm.me";
+        };
+      };
+    };
+
+    nginx = {
+      enable = lib.mkForce true;
+      virtualHosts = {
+        "grafana.0xtux.com" = {
+          forceSSL = true;
+          enableACME = true;
+          locations = {
+            "/" = {
+              proxyPass = "http://localhost:8888";
+              extraConfig = ''
+                proxy_set_header Host $host;
+              '';
+            };
+
+            "/api/live/" = {
+              proxyPass = "http://localhost:8888";
+              extraConfig = ''
+                proxy_http_version 1.1;
+                proxy_set_header Upgrade $http_upgrade;
+                proxy_set_header Connection $connection_upgrade;
+                proxy_set_header Host $host;
+              '';
+            };
+          };
+        };
+      };
+    };
+  };
+}