feat(ws): consume gateway change events (issue #784) (#837)

* feat(ws): consume gateway change events (cron/sessions/platforms/pairing) for targeted refresh (issue #784)

* test(chat): complete catch-all request stub — kill frozen-collector capture race (slash-focus flake, 4645a2b CI)

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Co-authored-by: M57 <hy4ri@users.noreply.github.com>

app/src/main/java/com/m57/hermescontrol/ui/channels/ChannelsViewModel.kt

@@ -9,7 +9,9 @@ import com.m57.hermescontrol.data.model.TelegramOnboardingStartRequest
 import com.m57.hermescontrol.data.model.TelegramOnboardingStartResponse
 import com.m57.hermescontrol.data.remote.ApiClient
 import com.m57.hermescontrol.data.remote.safeApiCall
+import com.m57.hermescontrol.data.ws.ChangeEvents
 import com.m57.hermescontrol.ui.common.ToastHost
+import com.m57.hermescontrol.ui.common.refreshOnChange
 import com.m57.hermescontrol.ui.common.safeLaunchLoad
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.delay
@@ -60,6 +62,24 @@ class ChannelsViewModel :
 
     private var launchJob: Job? = null
 
+    init {
+        // Issue #784: gateway broadcasts platforms.changed — refresh silently
+        // (no spinner) instead of waiting for a manual pull.
+        refreshOnChange(
+            eventType = ChangeEvents.PLATFORMS,
+            apiCall = { safeApiCall { ApiClient.hermesApi.getMessagingPlatforms() } },
+            onSuccess = { data ->
+                _uiState.update {
+                    it.copy(
+                        platforms = data.platforms.orEmpty(),
+                        gatewayStartCommand = data.gatewayStartCommand,
+                        envPath = data.envPath,
+                    )
+                }
+            },
+        )
+    }
+
     fun loadPlatforms() {
         safeLaunchLoad(
             apiCall = { safeApiCall { ApiClient.hermesApi.getMessagingPlatforms() } },