Add Phase 2 & 3: Web frontend with authentication and tracking features

- Initialize Next.js 14 web application with Material UI and TypeScript
- Implement authentication (login/register) with device fingerprint
- Create mobile-first responsive layout with app shell pattern
- Add tracking pages for feeding, sleep, and diaper changes
- Implement activity history with filtering
- Configure backend CORS for web frontend (port 3030)
- Update backend port to 3020, frontend to 3030
- Fix API response handling for auth endpoints

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

maternal-web/public/manifest.json

@@ -0,0 +1,26 @@
+{
+  "name": "Maternal Organization App",
+  "short_name": "Maternal",
+  "description": "AI-powered maternal and child care organization",
+  "start_url": "/",
+  "display": "standalone",
+  "background_color": "#FFF9F5",
+  "theme_color": "#FFB6C1",
+  "orientation": "portrait",
+  "icons": [
+    {
+      "src": "/icon-192x192.png",
+      "sizes": "192x192",
+      "type": "image/png",
+      "purpose": "any maskable"
+    },
+    {
+      "src": "/icon-512x512.png",
+      "sizes": "512x512",
+      "type": "image/png",
+      "purpose": "any maskable"
+    }
+  ],
+  "categories": ["health", "lifestyle", "productivity"],
+  "lang": "en-US"
+}