feat: initial commit — storefront, convex backend, and shared packages

Completes the first milestone of The Pet Loft ecommerce platform:
- apps/storefront: full customer-facing Next.js app with HeroUI (cart,
  checkout, orders, wishlist, product detail, shop, search, auth)
- convex/: serverless backend with schema, queries, mutations, actions,
  HTTP routes, Stripe/Shippo integrations, and co-located tests
- packages/types, packages/utils, packages/convex: shared workspace packages

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/storefront/tsconfig.json

@@ -0,0 +1,39 @@
+{
+  "compilerOptions": {
+    "lib": [
+      "dom",
+      "dom.iterable",
+      "esnext"
+    ],
+    "allowJs": true,
+    "skipLibCheck": true,
+    "strict": false,
+    "noEmit": true,
+    "incremental": true,
+    "module": "esnext",
+    "esModuleInterop": true,
+    "moduleResolution": "node",
+    "resolveJsonModule": true,
+    "isolatedModules": true,
+    "jsx": "preserve",
+    "plugins": [
+      {
+        "name": "next"
+      }
+    ],
+    "target": "ES2017",
+    "baseUrl": ".",
+    "paths": {
+      "@/*": ["./src/*"]
+    }
+  },
+  "include": [
+    "next-env.d.ts",
+    ".next/types/**/*.ts",
+    "**/*.ts",
+    "**/*.tsx"
+  ],
+  "exclude": [
+    "node_modules"
+  ]
+}