feat: Add keyboard shortcuts for navigation and action buttons

- Created use-keyboard-shortcuts hook to manage global keyboard shortcuts
- Added navigation shortcuts: K (Kanban), A (Agent), E (Spec Editor), C (Context), T (Tools), S (Settings)
- Added action shortcuts: N (Add Feature on board), F (Add File on context)
- Shortcuts automatically disabled when typing in inputs/textareas or when dialogs are open
- Display shortcut key indicators in navigation links and action buttons
- Added test utilities for keyboard shortcut testing

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/src/components/views/board-view.tsx

@@ -47,6 +47,11 @@ import { Plus, RefreshCw, Play, StopCircle, Loader2, ChevronUp, ChevronDown, Use
 import { toast } from "sonner";
 import { Slider } from "@/components/ui/slider";
 import { useAutoMode } from "@/hooks/use-auto-mode";
+import {
+  useKeyboardShortcuts,
+  ACTION_SHORTCUTS,
+  KeyboardShortcut,
+} from "@/hooks/use-keyboard-shortcuts";
 
 type ColumnId = Feature["status"];
 
@@ -98,6 +103,19 @@ export function BoardView() {
   // Auto mode hook
   const autoMode = useAutoMode();
 
+  // Keyboard shortcuts for this view
+  const boardShortcuts: KeyboardShortcut[] = useMemo(
+    () => [
+      {
+        key: ACTION_SHORTCUTS.addFeature,
+        action: () => setShowAddDialog(true),
+        description: "Add new feature",
+      },
+    ],
+    []
+  );
+  useKeyboardShortcuts(boardShortcuts);
+
   // Prevent hydration issues
   useEffect(() => {
     setIsMounted(true);
@@ -663,6 +681,12 @@ export function BoardView() {
           >
             <Plus className="w-4 h-4 mr-2" />
             Add Feature
+            <span
+              className="ml-2 px-1.5 py-0.5 text-[10px] font-mono rounded bg-white/10 border border-white/20"
+              data-testid="shortcut-add-feature"
+            >
+              {ACTION_SHORTCUTS.addFeature}
+            </span>
           </Button>
         </div>
       </div>