Add Medicine and Activity trackers with voice command support

Added new tracking pages:
- Medicine tracker: track medication name, dosage, unit, route, and reason
- Activity tracker: track play, exercise, walks, music, reading, tummy time, etc.
- Both pages follow existing tracker patterns with recent activities list

Voice command improvements:
- Updated voice classification to support medicine and activity types
- Added detailed extraction fields for medicine (medicineName, dosage, unit, route, reason)
- Added detailed extraction fields for activity (activityType, duration, description)
- Enhanced unknown intent dialog with manual tracker selection
- Updated tracker options to match implemented pages (removed milestone)

Backend changes:
- Added MEDICINE and ACTIVITY to ActivityType enum
- Created migration V013 to add medicine/activity to database CHECK constraint
- Updated voice service prompts to include medicine and activity extraction

Frontend changes:
- Created /track/medicine page with full CRUD operations
- Created /track/activity page with full CRUD operations
- Added Medicine card to /track page with MedicalServices icon
- Updated VoiceFloatingButton unknown dialog with 4 tracker options

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

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

maternal-web/app/track/page.tsx

@@ -1,7 +1,7 @@
 'use client';
 
 import { Box, Typography, Grid, Card, CardContent, CardActionArea } from '@mui/material';
-import { Restaurant, Hotel, BabyChangingStation, ChildCare } from '@mui/icons-material';
+import { Restaurant, Hotel, BabyChangingStation, ChildCare, MedicalServices } from '@mui/icons-material';
 import { useRouter } from 'next/navigation';
 import { AppShell } from '@/components/layouts/AppShell/AppShell';
 import { ProtectedRoute } from '@/components/common/ProtectedRoute';
@@ -28,6 +28,12 @@ export default function TrackPage() {
       path: '/track/diaper',
       color: '#FFF4E1',
     },
+    {
+      title: 'Medicine',
+      icon: <MedicalServices sx={{ fontSize: 48, color: 'error.main' }} />,
+      path: '/track/medicine',
+      color: '#FFE8E8',
+    },
     {
       title: 'Activity',
       icon: <ChildCare sx={{ fontSize: 48, color: 'success.main' }} />,