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/styles/utilities.css

@@ -383,129 +383,6 @@ a.nav-item,
 	align-items: center;
 }
 
-/* ============================================
-   Session Operations Progress Panel
-   ============================================ */
-
-.session-progress-panel {
-	position: fixed;
-	bottom: var(--space-4);
-	right: var(--space-4);
-	width: min(360px, calc(100vw - 2rem));
-	max-height: min(480px, 60vh);
-	overflow-y: auto;
-	background: var(--panel);
-	border: 1px solid var(--border);
-	border-radius: var(--space-2);
-	box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
-	z-index: 100;
-	display: flex;
-	flex-direction: column;
-}
-
-.session-progress-panel-header {
-	padding: var(--space-3) var(--space-4);
-	border-bottom: 1px solid var(--border);
-	font-weight: 600;
-	font-size: var(--text-sm);
-}
-
-.session-progress-panel-list {
-	display: flex;
-	flex-direction: column;
-	gap: var(--space-2);
-	padding: var(--space-3);
-}
-
-.session-operation-item {
-	padding: var(--space-3);
-	background: var(--bg);
-	border: 1px solid var(--border);
-	border-radius: var(--space-2);
-}
-
-.session-operation-item.error {
-	border-color: var(--danger);
-}
-
-.session-operation-header {
-	display: flex;
-	align-items: center;
-	justify-content: space-between;
-	gap: var(--space-2);
-}
-
-.session-operation-title {
-	display: flex;
-	align-items: center;
-	gap: var(--space-2);
-	min-width: 0;
-}
-
-.session-operation-title .icon {
-	flex-shrink: 0;
-}
-
-.session-operation-name {
-	font-weight: 600;
-	font-size: var(--text-sm);
-	white-space: nowrap;
-	overflow: hidden;
-	text-overflow: ellipsis;
-}
-
-.session-operation-message {
-	margin: var(--space-1) 0 0;
-	font-size: var(--text-xs);
-	color: var(--muted);
-}
-
-.session-operation-steps {
-	display: flex;
-	gap: var(--space-2);
-	margin-top: var(--space-2);
-}
-
-.session-operation-step {
-	font-size: 10px;
-	text-transform: uppercase;
-	letter-spacing: 0.03em;
-	color: var(--muted);
-	padding: 2px 6px;
-	border-radius: 4px;
-	background: var(--bg-muted);
-}
-
-.session-operation-step.active {
-	background: var(--primary);
-	color: var(--primary-fg);
-}
-
-.session-operation-step.current {
-	box-shadow: 0 0 0 1px var(--primary);
-}
-
-.session-operation-dismiss {
-	background: transparent;
-	border: none;
-	color: var(--muted);
-	cursor: pointer;
-	padding: var(--space-1);
-	display: flex;
-	align-items: center;
-	justify-content: center;
-}
-
-@media (max-width: 767px) {
-	.session-progress-panel {
-		left: var(--space-2);
-		right: var(--space-2);
-		bottom: calc(var(--space-2) + 64px);
-		width: auto;
-		max-height: 35vh;
-	}
-}
-
 /* ============================================
    Terminal Styles
    ============================================ */