feat: add command palette, accessibility, scroll animations, demo workspace, and keyboard navigation

- COMP-139: Command palette for quick navigation
- COMP-140: Accessibility improvements
- COMP-141: Scroll animations with animate-on-scroll component
- COMP-143: Demo workspace with seed data and demo banner
- COMP-145: Keyboard navigation and shortcuts help

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-Claude)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

apps/web/package.json

@@ -17,6 +17,7 @@
     "@xyflow/react": "^12.10.0",
     "bcryptjs": "^3.0.3",
     "clsx": "^2.1.1",
+    "cmdk": "^1.1.1",
     "ioredis": "^5.9.2",
     "lucide-react": "^0.469.0",
     "next": "^15.1.0",