docs(alerting): Add Matrix alerts to README

README.md

@@ -50,6 +50,7 @@ Have any feedback or questions? [Create a discussion](https://github.com/TwiN/ga
     - [Configuring Teams alerts](#configuring-teams-alerts)
     - [Configuring Telegram alerts](#configuring-telegram-alerts)
     - [Configuring Twilio alerts](#configuring-twilio-alerts)
+    - [Configuring Matrix alerts](#configuring-matrix-alerts)
     - [Configuring custom alerts](#configuring-custom-alerts)
     - [Setting a default alert](#setting-a-default-alert)
   - [Maintenance](#maintenance)
@@ -801,6 +802,36 @@ endpoints:
         description: "healthcheck failed"
 ```
 
+#### Configuring Matrix alerts
+| Parameter                          | Description                                                                                | Default                            |
+|:-----------------------------------|:-------------------------------------------------------------------------------------------|:-----------------------------------|
+| `alerting.matrix`                  | Settings for alerts of type `matrix`                                                       | `{}`                               |
+| `alerting.matrix.homeserver-url`   | Custom homeserver URL                                                                      | `https://matrix-client.matrix.org` |
+| `alerting.matrix.access-token`     | Bot user access token                                                                      | Required `""`                      |
+| `alerting.matrix.internal-room-id` | Internal room ID of room that bot user can send messages  to                               | Required `""`                      |
+| `alerting.matrix.default-alert`    | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A                                |
+
+```yaml
+alerting:
+  matrix:
+    homeserver-url: "..."
+    access-token: "..."
+    internal-room-id: "..."
+
+endpoints:
+  - name: website
+    interval: 30s
+    url: "https://twin.sh/health"
+    conditions:
+      - "[STATUS] == 200"
+      - "[BODY].status == UP"
+      - "[RESPONSE_TIME] < 300"
+    alerts:
+      - type: matrix
+        enabled: true
+        send-on-resolved: true
+        description: "healthcheck failed"
+```
 
 #### Configuring custom alerts
 | Parameter                       | Description                                                                                | Default       |