feat: initial web3 corporate style guide

- Extract design tokens (colors, typography, spacing) from dao-marketplace
- Build component CSS: base, card, button, forms
- Create interactive Vite showcase app with tabbed navigation
- Add README, .gitignore, AGENTS.md
- Build passes (vite v8.2.2)

tsconfig.json

@@ -0,0 +1,21 @@
+{
+  "compilerOptions": {
+    "target": "ES2020",
+    "useDefineForClassFields": true,
+    "lib": ["ES2020", "DOM", "DOM.Iterable"],
+    "module": "ESNext",
+    "skipLibCheck": true,
+    "moduleResolution": "bundler",
+    "allowImportingTsExtensions": true,
+    "isolatedModules": true,
+    "moduleDetection": "force",
+    "noEmit": true,
+    "jsx": "react-jsx",
+    "strict": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "noFallthroughCasesInSwitch": true,
+    "forceConsistentCasingInFileNames": true
+  },
+  "include": ["src"]
+}