feat: implement tool-session progress panel and live list updates

- Add SessionOperationsContext + SessionProgressPanel for global,
  non-blocking lifecycle progress (create/start/stop/restart/delete/
  recreate-tunnel) driven by SSE events.
- Promote SessionsContext to authoritative shared session state with
  refresh, addOrUpdateSession, and removeSession helpers.
- Wire AppShell, DashboardPage, SessionsPage, useInstanceActions,
  ToolStarter, and InstanceList into shared state so lists update
  immediately after create/delete without manual refresh.
- Remove legacy blocking overlays from CreateSessionForm, SessionCard,
  and InstanceList; keep disabled states and inline spinners only.
- Update DashboardPage tests to wrap with SessionsProvider and
  SessionOperationsProvider.
- Add .cache/ to .gitignore.

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

apps/web/src/components/features/tool/tool-starter.tsx

@@ -8,6 +8,8 @@ import {
 	type ConfigProfile,
 } from "../../../api/config-profiles";
 import { listSSHKeys, type SSHKey } from "../../../api/ssh-keys";
+import { useSessions } from "../../../state/sessions";
+import { useSessionOperations } from "../../../state/session-operations";
 import type { Workspace } from "../../../types/workspace";
 import type { ToolInstance } from "../../../api/sessions";
 
@@ -22,6 +24,8 @@ export function ToolStarter({
 	onStarted,
 	onCancel,
 }: ToolStarterProps) {
+	const { addOrUpdateSession } = useSessions();
+	const { startOperation } = useSessionOperations();
 	const [toolTypes, setToolTypes] = useState<ToolType[]>([]);
 	const [toolTypesLoading, setToolTypesLoading] = useState(true);
 	const [toolTypesError, setToolTypesError] = useState<string | null>(null);
@@ -141,6 +145,21 @@ export function ToolStarter({
 				selectedProfileId || undefined,
 				selectedSshKeyIds.length > 0 ? selectedSshKeyIds : undefined,
 			);
+			addOrUpdateSession({
+				id: instance.id,
+				display_name: instance.display_name,
+				tool_type_name: instance.tool_type_name,
+				tool_icon: "code",
+				tool_type_interfaces: instance.tool_type_interfaces || [],
+				repository_name: workspace.repo_name,
+				repository_id: workspace.repo_id,
+				project_name: workspace.project_name,
+				project_id: workspace.project_id,
+				workspace_name: workspace.name,
+				status: instance.status || "pending",
+				url: instance.url || null,
+			});
+			startOperation("create", instance.id, instance.display_name);
 			onStarted(instance);
 		} catch (err) {
 			setError(err instanceof Error ? err.message : "Failed to start tool");
@@ -153,6 +172,9 @@ export function ToolStarter({
 		displayName,
 		workspace,
 		onStarted,
+		toolTypes,
+		addOrUpdateSession,
+		startOperation,
 	]);
 
 	return (