Add Event platform description to watergate documentation

source/_integrations/watergate.markdown

@@ -14,6 +14,7 @@ ha_domain: watergate
 ha_platforms:
   - valve
   - sensor
+  - event
 ---
 
 The **Watergate** integration integrates your Watergate Devices (currently Sonic Wi-Fi) with your Home Assistant.
@@ -22,6 +23,7 @@ With this integration, you are able to:
 - Control your valve
 - Monitor live telemetry (water flow, water pressure, water temperature)
 - Monitor water usage
+- Receive information when Sonic shuts off the valve due to potential leak
 
 ## Prerequisites
 
@@ -69,6 +71,16 @@ The Watergate integration provides the following entities.
 - **Water valve state**
   - **Description**: The current state of the water valve (open/closed).
   - **Remarks**: It is automatically updated when the valve state is changed.
+
+#### Events
+
+- **Auto Shut-Off**
+  - **Description**: Event triggered when the valve automatically shuts off due to detected leak.
+  - **Event Type**: Either `volume_threshold` or `duration_threshold`
+  - **Event Data**:
+    - `volume`: The volume of water that triggered the shut-off
+    - `duration`: The duration of leak that triggered the shut-off
+  - **Remarks**: Historical events are not preserved across Home Assistant restarts.
 
 ## Data updates
 
@@ -77,7 +89,7 @@ Thanks to the webhook option, Sonic will provide live telemetry every second whe
 
 ## Known limitations
 
-The integration does not provide the ability to set auto shut-off thresholds and does not report any events regarding automatically closed valves.
+The integration does not provide the ability to set auto shut-off thresholds.
 
 {% include integrations/config_flow.md %}