fix(#1197): advertise server request capability (#1198)

app/src/main/java/com/m57/hermescontrol/data/ws/HermesWsClient.kt

@@ -354,6 +354,14 @@ object HermesWsClient {
         wsScope.launch {
             events.collect { event ->
                 if (event is WsEvent.GatewayReady) {
+                    // Advertise support for gateway server→client requests (issue #1197).
+                    // Older gateways may reject this method; that is harmless.
+                    runCatching {
+                        send(
+                            WsMethods.CLIENT_CAPABILITIES,
+                            mapOf("server_requests" to true),
+                        )
+                    }
                     val epoch = event.data?.get("replay_epoch") as? String
                     if (!epoch.isNullOrEmpty()) {
                         if (replayEpoch != null && replayEpoch != epoch) {

app/src/main/java/com/m57/hermescontrol/data/ws/WsMethods.kt

@@ -66,6 +66,7 @@ object WsMethods {
 
     /** Inline WebSocket read-loop ping, bypasses server thread pool dispatch. */
     const val GATEWAY_PING = "gateway.ping"
+    const val CLIENT_CAPABILITIES = "client.capabilities"
 
     // ── Commands catalog ──────────────────────────────────────────────────
     const val COMMANDS_CATALOG = "commands.catalog"

app/src/test/java/com/m57/hermescontrol/data/ws/HermesWsClientTest.kt

@@ -176,6 +176,51 @@ class HermesWsClientTest {
         assertTrue(msg.contains(id))
     }
 
+    @Test
+    fun gatewayReadyAdvertisesServerRequestCapability() {
+        val capabilityLatch = CountDownLatch(1)
+        var capabilityFrame: String? = null
+
+        mockWebServer.enqueue(
+            MockResponse().withWebSocketUpgrade(
+                object : WebSocketListener() {
+                    override fun onOpen(
+                        webSocket: WebSocket,
+                        response: okhttp3.Response,
+                    ) {
+                        webSocket.send(
+                            """{"jsonrpc":"2.0","method":"event","params":{"type":"gateway.ready","payload":{}}}""",
+                        )
+                    }
+
+                    override fun onMessage(
+                        webSocket: WebSocket,
+                        text: String,
+                    ) {
+                        val frame = Json.parseToJsonElement(text).jsonObject
+                        if (frame["method"]?.jsonPrimitive?.content == WsMethods.CLIENT_CAPABILITIES) {
+                            capabilityFrame = text
+                            capabilityLatch.countDown()
+                        }
+                    }
+                },
+            ),
+        )
+
+        HermesWsClient.connect()
+
+        assertTrue("Capability advertisement not sent", capabilityLatch.await(5, TimeUnit.SECONDS))
+        val frame = Json.parseToJsonElement(capabilityFrame ?: "{}").jsonObject
+        assertEquals(WsMethods.CLIENT_CAPABILITIES, frame["method"]?.jsonPrimitive?.content)
+        assertTrue(
+            frame["params"]
+                ?.jsonObject
+                ?.get("server_requests")
+                ?.jsonPrimitive
+                ?.content == "true",
+        )
+    }
+
     @Test
     fun testOpenRequestsReplayUsesTheLiveServerRequestDispatcher() =
         runBlocking {