feat(01-01): scaffold Vite project with CSS design system and project structure

- Vite 6 + TypeScript + Biome + Vitest configured
- All directories from spec section 13 created
- CSS custom properties for full color palette and finger colors
- index.html with 5 screen sections and Google Fonts
- Dev server binds to 0.0.0.0:5173 for VPS access

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

public/config.example.json

@@ -0,0 +1,5 @@
+{
+	"geminiApiKey": "YOUR_API_KEY_HERE",
+	"geminiModel": "gemini-2.5-flash",
+	"imageModel": "gemini-3.1-flash-image-preview"
+}