feat(web): workspace components — ComparePane, Memory page, McpDialog, error boundaries, message-parts

- Add ComparePane.tsx: side-by-side AI response comparison
- Add Memory.tsx: memory management page with CRUD UI
- Add McpPermissionDialog.tsx: MCP tool permission approval dialog
- Add McpResponseDisplay.tsx: MCP response visualization
- Add MessageBoundary.tsx + MessageListErrorBoundary.tsx: error resilience
- Add EmptyState.tsx: contextual empty state component
- Add KeyboardShortcutsDialog.tsx: keyboard shortcut reference
- Add message-parts/: ActionRow, CompactCard, MistakeRecoverySentinel, ReasoningBlock, SendToTerminalMenu, StatsLine, SummaryCard
- Add useDraftPersistence.ts: draft message persistence hook
- Add useTerminals.ts: terminal session management hook
- Add keyboard-shortcuts.ts + tool-utils.ts: shared utilities
- Extend components: ChatInput, MessageBubble, MessageList, Workspace, panes
- Extend hooks: useTerminalSocket, useSessionStream test suite
- Update pages: Home, Project — workspace layout and session flow

apps/web/src/components/ToolCallGroup.tsx

@@ -33,11 +33,20 @@ export function ToolCallGroup({ runs }: Props) {
     <div className="rounded border border-border/60 bg-muted/20 text-xs">
       <button
         type="button"
+        tabIndex={0}
         onClick={() => setOpen((v) => !v)}
-        className="w-full flex items-center gap-1.5 px-2 py-1 hover:bg-muted/40 text-left"
+        onKeyDown={(e) => {
+          if (e.key === 'Enter' || e.key === ' ') {
+            e.preventDefault();
+            setOpen((v) => !v);
+          } else if (e.key === 'Escape') {
+            setOpen(false);
+          }
+        }}
+        className="w-full flex items-center gap-1.5 px-2 py-1 hover:bg-muted/40 text-left focus-visible:ring-2 focus-visible:ring-ring focus-visible:ring-offset-1"
       >
         <ChevronRight
-          className={`size-3 text-muted-foreground/60 shrink-0 transition-transform ${open ? 'rotate-90' : ''}`}
+          className={`size-3 text-muted-foreground/60 shrink-0 motion-reduce:transition-none transition-transform ${open ? 'rotate-90' : ''}`}
         />
         <span className="text-muted-foreground/60 select-none shrink-0">⊞</span>
         <span className="font-mono text-foreground/90">