Feat: Improve Docs (#1791)

* improve docs

* preplan guides

* fix spelling

* fix nftables rules

* consistent wg-easy code block

* fix grammar

docs/content/advanced/metrics/prometheus.md

@@ -2,6 +2,41 @@
 title: Prometheus
 ---
 
-TODO
+To monitor the WireGuard server, you can use [Prometheus](https://prometheus.io/) and [Grafana](https://grafana.com/). The container exposes a `/metrics/prometheus` endpoint that can be scraped by Prometheus.
 
-<!-- TOOD: add to docs: Grafana dashboard [21733](https://grafana.com/grafana/dashboards/21733-wireguard/) -->
+## Enable Prometheus
+
+To enable Prometheus metrics, go to Admin Panel > General and enable Prometheus.
+
+You can optionally set a Bearer Password for the metrics endpoints. This is useful if you want to expose the metrics endpoint to the internet.
+
+## Configure Prometheus
+
+You need to add a scrape config to your Prometheus configuration file. Here is an example:
+
+```yaml
+scrape_configs:
+  - job_name: "wg-easy"
+    scrape_interval: 30s
+    metrics_path: /metrics/prometheus
+    static_configs:
+      - targets:
+          - "localhost:51821"
+    authorization:
+      type: Bearer
+      credentials: "SuperSecurePassword"
+```
+
+## Grafana Dashboard
+
+You can use the following Grafana dashboard to visualize the metrics:
+
+[![Grafana Dashboard](https://grafana.com/api/dashboards/21733/images/16863/image)](https://grafana.com/grafana/dashboards/21733-wireguard/)
+
+[21733](https://grafana.com/grafana/dashboards/21733-wireguard/)
+
+/// note | Unofficial
+
+The Grafana dashboard is not official and is not maintained by the `wg-easy` team. If you have any issues with the dashboard, please contact the author of the dashboard.
+See [#1299](https://github.com/wg-easy/wg-easy/pull/1299) for more information.
+///