feat: setup frontend con pnpm, vite, react, tailwind y shadcn

Inicializa directorio frontend/ con stack React moderno:
pnpm + vite 8 + react 19 + tailwind v4 + shadcn v4 (base-nova).
Estructura functions/core (TS puro) y functions/ui (componentes React).
El indexer descubre frontend/functions/ y frontend/types/ automáticamente.
Elimina functions/components/ (legacy) y actualiza referencias en
CLAUDE.md y template de componentes.

frontend/tsconfig.json

@@ -0,0 +1,25 @@
+{
+  "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,
+    "noUncheckedIndexedAccess": true,
+    "paths": {
+      "@/*": ["./src/*"]
+    },
+    "ignoreDeprecations": "6.0"
+  },
+  "include": ["src", "functions", "types"]
+}