feat: Implement Phase 1 Shopify-inspired settings (Store, Payments, Shipping)

✨ Features:
- Store Details page with live currency preview
- Payments page with visual provider cards and test mode
- Shipping & Delivery page with zone cards and local pickup
- Shared components: SettingsLayout, SettingsCard, SettingsSection, ToggleField

🎨 UI/UX:
- Card-based layouts (not boring forms)
- Generous whitespace and visual hierarchy
- Toast notifications using sonner (reused from Orders)
- Sticky save button at top
- Mobile-responsive design

🔧 Technical:
- Installed ESLint with TypeScript support
- Fixed all lint errors (0 errors)
- Phase 1 files have zero warnings
- Used existing toast from sonner (not reinvented)
- Updated routes in App.tsx

📝 Files Created:
- Store.tsx (currency preview, address, timezone)
- Payments.tsx (provider cards, manual methods)
- Shipping.tsx (zone cards, rates, local pickup)
- SettingsLayout.tsx, SettingsCard.tsx, SettingsSection.tsx, ToggleField.tsx

Phase 1 complete: 18-24 hours estimated work

admin-spa/package.json

@@ -6,7 +6,8 @@
     "scripts": {
         "dev": "vite --host woonoow.local --port 5173 --strictPort",
         "build": "vite build",
-        "preview": "vite preview --port 5173"
+        "preview": "vite preview --port 5173",
+        "lint": "ESLINT_USE_FLAT_CONFIG=false eslint . --ext ts,tsx --report-unused-disable-directives"
     },
     "dependencies": {
         "@radix-ui/react-avatar": "^1.1.10",
@@ -39,8 +40,14 @@
     "devDependencies": {
         "@types/react": "^18.3.5",
         "@types/react-dom": "^18.3.0",
+        "@typescript-eslint/eslint-plugin": "^8.46.3",
+        "@typescript-eslint/parser": "^8.46.3",
         "@vitejs/plugin-react": "^5.1.0",
         "autoprefixer": "^10.4.21",
+        "eslint": "^9.39.1",
+        "eslint-plugin-react": "^7.37.5",
+        "eslint-plugin-react-hooks": "^7.0.1",
+        "eslint-plugin-react-refresh": "^0.4.24",
         "postcss": "^8.5.6",
         "tailwindcss": "^3.4.13",
         "tailwindcss-animate": "^1.0.7",