fix: listen for named SSE events in progress panel

The backend sends named lifecycle events (event: instance.health_changed),
but useEvents only set es.onmessage, which only receives unnamed message
events. Add explicit addEventListener registrations for all lifecycle
event types so the progress panel receives updates and completes.

Quality gates: npm run typecheck, npm run lint, npm test -- --run
(87 passed).

apps/web/src/hooks/use-events.test.ts

@@ -14,10 +14,13 @@ const mockedCreateEventSource = vi.mocked(createEventSource);
 const mockedProbeEventStreamStatus = vi.mocked(probeEventStreamStatus);
 
 describe("useEvents", () => {
-	let mockEs: EventSource;
+	let mockEs: EventSource & {
+		emit: (type: string, data: string) => void;
+	};
 
 	beforeEach(() => {
 		vi.useFakeTimers({ shouldAdvanceTime: true });
+		const listeners = new Map<string, Set<(e: MessageEvent) => void>>();
 		mockEs = {
 			close: vi.fn(),
 			onopen: null,
@@ -27,7 +30,17 @@ describe("useEvents", () => {
 				return EventSource.OPEN;
 			},
 			url: "http://localhost:8000/events/stream",
-		} as unknown as EventSource;
+			addEventListener: vi.fn((type: string, handler: (e: MessageEvent) => void) => {
+				if (!listeners.has(type)) listeners.set(type, new Set());
+				listeners.get(type)!.add(handler);
+			}),
+			removeEventListener: vi.fn((type: string, handler: (e: MessageEvent) => void) => {
+				listeners.get(type)?.delete(handler);
+			}),
+			emit: (type: string, data: string) => {
+				listeners.get(type)?.forEach((handler) => handler({ data } as MessageEvent));
+			},
+		} as unknown as EventSource & { emit: (type: string, data: string) => void };
 		mockedCreateEventSource.mockReturnValue(mockEs);
 		mockedProbeEventStreamStatus.mockResolvedValue(null);
 	});
@@ -56,9 +69,7 @@ describe("useEvents", () => {
 		};
 
 		act(() => {
-			mockEs.onmessage?.({
-				data: JSON.stringify(payload),
-			} as MessageEvent);
+			mockEs.emit("instance.started", JSON.stringify(payload));
 		});
 
 		await waitFor(() => {

apps/web/src/hooks/use-events.ts

@@ -12,6 +12,16 @@ export interface UseEventsReturn {
 const MAX_DELAY = 30000;
 const BASE_DELAY = 1000;
 
+const LIFECYCLE_EVENT_TYPES = [
+	"instance.created",
+	"instance.started",
+	"instance.stopped",
+	"instance.restarted",
+	"instance.deleted",
+	"instance.error",
+	"instance.health_changed",
+] as const;
+
 export function useEvents(): UseEventsReturn {
 	const [events, setEvents] = useState<InstanceEventPayload[]>([]);
 	const [connected, setConnected] = useState(false);
@@ -39,7 +49,7 @@ export function useEvents(): UseEventsReturn {
 			setReconnectCount(0);
 		};
 
-		es.onmessage = (e) => {
+		const handleEventMessage = (e: MessageEvent) => {
 			if (!isMountedRef.current) return;
 			try {
 				const payload: InstanceEventPayload = JSON.parse(e.data);
@@ -49,6 +59,11 @@ export function useEvents(): UseEventsReturn {
 			}
 		};
 
+		es.addEventListener("message", handleEventMessage);
+		for (const eventType of LIFECYCLE_EVENT_TYPES) {
+			es.addEventListener(eventType, handleEventMessage);
+		}
+
 		es.onerror = () => {
 			if (!isMountedRef.current) return;
 			setConnected(false);