docs(zigbee2mqtt): helmify docs (#32979)

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charts/stable/zigbee2mqtt/docs/installation.md

@@ -2,29 +2,45 @@
 title: Installation Guide
 ---
 
-## TrueNAS SCALE Installation Hints
+## How-To
 
 Here's an example of a default installation of zigbee2mqtt. Pay particular attention to the section "Configure Mount USB Devices" to configure the USB adapter to your container as those two paths should match.
 
-### Application Configuration
+### Deployment Configuration
 
-Enter `MQTT User`, `MQTT Password` if necessary, as this will override the specific value of config file. Leave empty if you plan to use custom config or you don't have set a user on your MQTT broker.
+Set `ZIGBEE2MQTT_CONFIG_MQTT_USER`, `ZIGBEE2MQTT_CONFIG_MQTT_PASSWORD` if necessary, as this will override the specific value of config file. Leave empty if you plan to use custom config or you don't have set a user on your MQTT broker.
 
-For `MQTT Server` Internal DNS Cluster IP can be used (default) of `mqtt://mosquitto.ix-mosquitto.svc.cluster.local` or you can use the external IP.
+For `MQTT Server` Internal DNS Cluster IP can be used (default) of `mqtt://mosquitto.mosquitto.svc.cluster.local` or you can use the external IP.
 
-![config1](./images/config1.png)
-![config1](./images/config1.png)
-![config2](./images/config2.png)
-![config3](./images/config3.png)
-![config4](./images/config4.png)
-![config5](./images/config5.png)
+```yaml
+workload:
+  main:
+    podSpec:
+      containers:
+        main:
+          env:
+            USE_CUSTOM_CONFIG_FILE: false
+            # This values are required for the autogenerated file to work.
+            # ZIGBEE2MQTT_CONFIG_PERMIT_JOIN: false
+            ZIGBEE2MQTT_CONFIG_MQTT_SERVER: "mqtt://mosquitto.mosquitto.svc.cluster.local"
+            ZIGBEE2MQTT_CONFIG_MQTT_BASE_TOPIC: "zigbee2mqtt"
+            ZIGBEE2MQTT_CONFIG_SERIAL_PORT: "/dev/ttyUSB0"
+            ZIGBEE2MQTT_CONFIG_SERIAL_ADAPTER: "auto"
+            ZIGBEE2MQTT_CONFIG_MQTT_USER: "mqtt_user"
+            ZIGBEE2MQTT_CONFIG_MQTT_PASSWORD: "secretpassword"
+```
 
 ### Mount USB Devices
 
-Make sure `Enable the Storage is Checked` and enter your USB device by ID as per below, in this example we use `/dev/serial/by-id/usb-ithead_SONOFF`
+- Passthrough your USB device to your cluster node. 
+- Add a persistence configuration for your USB device
+- Best practice is to do by ID as per below, in this example we use `/dev/serial/by-id/usb-ithead_SONOFF`
 
-![config6](./images/config6.png)
+```yaml
+persistence:
+  zigbee:
+    enabled: true
+    type: device
+    hostPath: /dev/serial/by-id/usb-ithead_SONOFF
+```
 
-This guide should prevent one of the following error messages:
-![error message 1](./images/error_log1.png)
-![error message 2](./images/error_log2.png)