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/test/java/com/m57/hermescontrol/ui/chat/ChatViewModelTest.kt

@@ -101,11 +101,13 @@ class ChatViewModelTest {
         // fires after unmockkAll and crashes an unrelated later test with
         // MockK's "can't find stub" (UncaughtExceptionsBeforeTest). Mirror
         // the real request()'s send() delegation (tests verify send calls)
-        // but return a never-completing deferred — same unanswered behavior,
-        // no leaked timer.
+        // but skip the timer. Must COMPLETE (Unit): a never-completing
+        // deferred freezes the VM's event collector at the SESSION_CREATE
+        // session.usage await and lets its late completion race per-test
+        // capture stubs (slash-focus flake, CI 31137581335 on 4645a2b).
         every { HermesWsClient.request(any(), any(), any()) } answers {
             HermesWsClient.send(arg(0), arg(1)) {}
-            CompletableDeferred<Any?>()
+            CompletableDeferred<Any?>(Unit)
         }
         mockkObject(ApiClient)
         mockkObject(HermesDatabase)

app/src/test/java/com/m57/hermescontrol/ui/chat/SlashCommandDispatchRpcTest.kt

@@ -107,10 +107,15 @@ class SlashCommandDispatchRpcTest {
         // wsScope that fires after unmockkAll and crashes a later test with
         // MockK's "can't find stub". Mirror the real send() delegation (so
         // send-based verifications still see the call) but skip the timer.
+        // Must COMPLETE (Unit): a never-completing deferred freezes the VM's
+        // event collector at the SESSION_CREATE-triggered session.usage await,
+        // and that completion then races the per-test capture stubs — the slot
+        // can end up holding session.usage instead of command.dispatch (CI run
+        // 31137581335 on 4645a2b: slash-focus flake).
         // Specific per-test request() stubs registered later take precedence.
         every { HermesWsClient.request(any(), any(), any()) } answers {
             HermesWsClient.send(arg(0), arg(1)) {}
-            CompletableDeferred<Any?>()
+            CompletableDeferred<Any?>(Unit)
         }
     }