remove: session operations center and progress panel

The bottom-right progress panel duplicated feedback already shown by
toasts. Remove it and the operation-tracking state to simplify the UI:

- Delete state/session-operations.tsx and session-progress-panel.tsx.
- Remove SessionOperationsProvider/SessionProgressPanel from AppShell.
- Remove startOperation/completeOperation calls from useInstanceActions
  and ToolStarter.
- Remove SessionOperationsProvider wrapper from DashboardPage.test.tsx.
- Remove .session-progress-panel CSS rules.
- Format use-events.test.ts mock to match project lint rules.

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

apps/web/src/hooks/use-instance-actions.ts

@@ -8,7 +8,6 @@ import {
 } from "../api/sessions";
 import type { Session } from "../api/sessions";
 import { useSessions } from "../state/sessions";
-import { useSessionOperations } from "../state/session-operations";
 
 interface UseInstanceActionsOptions {
 	onRefresh: () => Promise<void>;
@@ -33,7 +32,6 @@ export function useInstanceActions(
 ): UseInstanceActionsReturn {
 	const { onRefresh } = options;
 	const { removeSession } = useSessions();
-	const { startOperation, completeOperation } = useSessionOperations();
 	const [loadingSessionId, setLoadingSessionId] = useState<string | null>(null);
 	const [dirtyDeleteSession, setDirtyDeleteSession] = useState<Session | null>(
 		null,
@@ -66,7 +64,6 @@ export function useInstanceActions(
 		async (session: Session) => {
 			if (loadingSessionId === session.id) return;
 			setLoadingSessionId(session.id);
-			startOperation("start", session.id, session.display_name);
 			try {
 				await startInstance(
 					session.project_id,
@@ -74,20 +71,17 @@ export function useInstanceActions(
 					session.id,
 				);
 				await onRefresh();
-			} catch {
-				completeOperation(session.id, "start", "error");
 			} finally {
 				setLoadingSessionId(null);
 			}
 		},
-		[loadingSessionId, onRefresh, startOperation, completeOperation],
+		[loadingSessionId, onRefresh],
 	);
 
 	const handleStop = useCallback(
 		async (session: Session) => {
 			if (loadingSessionId === session.id) return;
 			setLoadingSessionId(session.id);
-			startOperation("stop", session.id, session.display_name);
 			try {
 				await stopInstance(
 					session.project_id,
@@ -95,20 +89,17 @@ export function useInstanceActions(
 					session.id,
 				);
 				await onRefresh();
-			} catch {
-				completeOperation(session.id, "stop", "error");
 			} finally {
 				setLoadingSessionId(null);
 			}
 		},
-		[loadingSessionId, onRefresh, startOperation, completeOperation],
+		[loadingSessionId, onRefresh],
 	);
 
 	const handleDelete = useCallback(
 		async (session: Session) => {
 			if (loadingSessionId === session.id) return;
 			setLoadingSessionId(session.id);
-			startOperation("delete", session.id, session.display_name);
 			try {
 				await deleteInstance(
 					session.project_id,
@@ -120,7 +111,6 @@ export function useInstanceActions(
 				removeSession(session.id);
 				await onRefresh();
 			} catch (error) {
-				completeOperation(session.id, "delete", "error");
 				const axiosError = error as {
 					response?: {
 						status?: number;
@@ -139,20 +129,13 @@ export function useInstanceActions(
 				setLoadingSessionId(null);
 			}
 		},
-		[
-			loadingSessionId,
-			onRefresh,
-			removeSession,
-			startOperation,
-			completeOperation,
-		],
+		[loadingSessionId, onRefresh, removeSession],
 	);
 
 	const handleForceDelete = useCallback(
 		async (session: Session) => {
 			if (loadingSessionId === session.id) return;
 			setLoadingSessionId(session.id);
-			startOperation("delete", session.id, session.display_name);
 			try {
 				await deleteInstance(
 					session.project_id,
@@ -164,26 +147,17 @@ export function useInstanceActions(
 				setDirtyDeleteFiles([]);
 				removeSession(session.id);
 				await onRefresh();
-			} catch {
-				completeOperation(session.id, "delete", "error");
 			} finally {
 				setLoadingSessionId(null);
 			}
 		},
-		[
-			loadingSessionId,
-			onRefresh,
-			removeSession,
-			startOperation,
-			completeOperation,
-		],
+		[loadingSessionId, onRefresh, removeSession],
 	);
 
 	const handleRecreateTunnel = useCallback(
 		async (session: Session) => {
 			if (loadingSessionId === session.id) return;
 			setLoadingSessionId(session.id);
-			startOperation("recreate-tunnel", session.id, session.display_name);
 			try {
 				await recreateInstanceTunnel(
 					session.project_id,
@@ -191,18 +165,16 @@ export function useInstanceActions(
 					session.id,
 				);
 				await onRefresh();
-				completeOperation(session.id, "recreate-tunnel", "success");
 			} catch (err) {
 				const message =
 					(err as { response?: { data?: { detail?: string } } })?.response?.data
 						?.detail || "Failed to recreate tunnel";
-				completeOperation(session.id, "recreate-tunnel", "error", message);
 				alert(message);
 			} finally {
 				setLoadingSessionId(null);
 			}
 		},
-		[loadingSessionId, onRefresh, startOperation, completeOperation],
+		[loadingSessionId, onRefresh],
 	);
 
 	const handleRename = useCallback(