Add documentation for new configuration option

Author: anoadragon453

docs/usage/configuration/config_documentation.md

@@ -2575,6 +2575,28 @@ Example configuration:
 turn_allow_guests: false
 ```
 ---
+### `matrix_rtc`
+
+*(object)* Options related to MatrixRTC. Defaults to `{}`.
+
+This setting has the following sub-options:
+
+* `transports` (array): A list of transport types and arguments to use for MatrixRTC connections. Defaults to `[]`.
+
+  Options for each entry include:
+
+  * `type` (string): The type of transport to use to connect to the selective forwarding unit (SFU).
+
+  * `livekit_service_url` (string): The base URL of the LiveKit service. Should only be used with LiveKit-based transports.
+
+Example configuration:
+```yaml
+matrix_rtc:
+  transports:
+  - type: livekit
+    livekit_service_url: https://matrix-rtc.example.com/livekit/jwt
+```
+---
 ## Registration
 
 Registration can be rate-limited using the parameters in the [Ratelimiting](#ratelimiting) section of this manual.

schema/synapse-config.schema.yaml

@@ -2886,6 +2886,35 @@ properties:
     default: true
     examples:
       - false
+  matrix_rtc:
+    type: object 
+    description: >-
+      Options related to MatrixRTC.
+    properties:
+      transports:
+        type: array
+        items:
+          type: object
+          required:
+            - type
+          properties:
+            type:
+              type: string
+              description: The type of transport to use to connect to the selective forwarding unit (SFU).
+              example: livekit
+            livekit_service_url:
+              type: string
+              description: >-
+                The base URL of the LiveKit service. Should only be used with LiveKit-based transports.
+              example: https://matrix-rtc.example.com/livekit/jwt
+        description:
+          A list of transport types and arguments to use for MatrixRTC connections.
+        default: []
+    default: {}
+    examples:
+      - transports:
+        - type: livekit
+          livekit_service_url: https://matrix-rtc.example.com/livekit/jwt
   enable_registration:
     type: boolean
     description: >-