feat: Complete comprehensive localization of all tracking and management pages

- Feeding page: 47+ strings localized with validation, success/error messages
- Medicine page: 44 strings localized with unit conversion support
- Sleep page: Already localized (verified)
- Diaper page: Already localized (verified)
- Activity page: Already localized (verified)
- AI Assistant: 51 strings localized including chat interface and suggested questions
- Children page: 38 strings fully localized with gender labels
- Family page: 42 strings localized with role management
- Insights page: 41 strings localized including charts and analytics

Added translation files:
- locales/en/ai.json (44 keys)
- locales/en/family.json (42 keys)
- locales/en/insights.json (41 keys)

Updated translation files:
- locales/en/tracking.json (added feeding, health/medicine sections)
- locales/en/children.json (verified complete)

All pages now use useTranslation hook with proper namespaces.
All user-facing text externalized and ready for multi-language support.

maternal-web/app/track/medicine/page.tsx

@@ -114,7 +114,7 @@ function MedicineTrackPage() {
       }
     } catch (err: any) {
       console.error('Failed to load children:', err);
-      setError(err.response?.data?.message || 'Failed to load children');
+      setError(err.response?.data?.message || t('common.error.loadChildrenFailed'));
     } finally {
       setChildrenLoading(false);
     }
@@ -140,19 +140,19 @@ function MedicineTrackPage() {
 
   const handleSubmit = async () => {
     if (!selectedChild) {
-      setError('Please select a child');
+      setError(t('common.selectChild'));
       return;
     }
 
     // Validation
     if (!medicineName) {
-      setError('Please enter medicine name');
+      setError(t('health.medicineName.required'));
       return;
     }
 
     const dosageValue = unit === 'ml' ? dosage : dosageText;
     if (!dosageValue || (unit === 'ml' && dosage === 0) || (unit !== 'ml' && !dosageText)) {
-      setError('Please enter dosage');
+      setError(t('health.dosage.required'));
       return;
     }
 
@@ -175,7 +175,7 @@ function MedicineTrackPage() {
         notes: notes || undefined,
       });
 
-      setSuccessMessage('Medicine logged successfully!');
+      setSuccessMessage(t('health.success'));
 
       // Reset form
       resetForm();
@@ -184,7 +184,7 @@ function MedicineTrackPage() {
       await loadRecentMedicines();
     } catch (err: any) {
       console.error('Failed to save medicine:', err);
-      setError(err.response?.data?.message || 'Failed to save medicine');
+      setError(err.response?.data?.message || t('health.error'));
     } finally {
       setLoading(false);
     }
@@ -211,13 +211,13 @@ function MedicineTrackPage() {
     try {
       setLoading(true);
       await trackingApi.deleteActivity(activityToDelete);
-      setSuccessMessage('Medicine deleted successfully');
+      setSuccessMessage(t('health.deleted'));
       setDeleteDialogOpen(false);
       setActivityToDelete(null);
       await loadRecentMedicines();
     } catch (err: any) {
       console.error('Failed to delete medicine:', err);
-      setError(err.response?.data?.message || 'Failed to delete medicine');
+      setError(err.response?.data?.message || t('health.deleteError'));
     } finally {
       setLoading(false);
     }
@@ -282,17 +282,17 @@ function MedicineTrackPage() {
             <CardContent sx={{ textAlign: 'center', py: 8 }}>
               <ChildCare sx={{ fontSize: 64, color: 'text.secondary', mb: 2 }} />
               <Typography variant="h6" color="text.secondary" gutterBottom>
-                No Children Added
+                {t('common.noChildrenAdded')}
               </Typography>
               <Typography variant="body2" color="text.secondary" sx={{ mb: 3 }}>
-                You need to add a child before you can track medicine activities
+                {t('common.noChildrenMessage')}
               </Typography>
               <Button
                 variant="contained"
                 startIcon={<Add />}
                 onClick={() => router.push('/children')}
               >
-                Add Child
+                {t('common.addChild')}
               </Button>
             </CardContent>
           </Card>
@@ -352,11 +352,11 @@ function MedicineTrackPage() {
             {children.length > 1 && (
               <Paper sx={{ p: 2, mb: 3 }}>
                 <FormControl fullWidth>
-                  <InputLabel>Select Child</InputLabel>
+                  <InputLabel>{t('common.selectChild')}</InputLabel>
                   <Select
                     value={selectedChild}
                     onChange={(e) => setSelectedChild(e.target.value)}
-                    label="Select Child"
+                    label={t('common.selectChild')}
                   >
                     {children.map((child) => (
                       <MenuItem key={child.id} value={child.id}>
@@ -373,17 +373,17 @@ function MedicineTrackPage() {
               <Box sx={{ display: 'flex', alignItems: 'center', mb: 3 }}>
                 <MedicalServices sx={{ fontSize: 36, color: 'error.main', mr: 2 }} />
                 <Typography variant="h6" fontWeight="600">
-                  Medicine Information
+                  {t('health.medicineInfo')}
                 </Typography>
               </Box>
 
               <TextField
                 fullWidth
-                label="Medicine Name"
+                label={t('health.medicineName.label')}
                 value={medicineName}
                 onChange={(e) => setMedicineName(e.target.value)}
                 sx={{ mb: 3 }}
-                placeholder="e.g., Acetaminophen, Ibuprofen"
+                placeholder={t('health.medicineName.placeholder')}
                 required
               />
 
@@ -391,7 +391,7 @@ function MedicineTrackPage() {
                 {unit === 'ml' ? (
                   <UnitInput
                     fullWidth
-                    label="Dosage"
+                    label={t('health.dosage.label')}
                     type="volume"
                     value={dosage}
                     onChange={(metricValue) => setDosage(metricValue)}
@@ -400,16 +400,16 @@ function MedicineTrackPage() {
                 ) : (
                   <TextField
                     fullWidth
-                    label="Dosage"
+                    label={t('health.dosage.label')}
                     value={dosageText}
                     onChange={(e) => setDosageText(e.target.value)}
-                    placeholder="e.g., 5, 2.5"
+                    placeholder={t('health.dosage.placeholder')}
                     required
                   />
                 )}
 
                 <FormControl fullWidth>
-                  <InputLabel>Unit</InputLabel>
+                  <InputLabel>{t('health.unit')}</InputLabel>
                   <Select
                     value={unit}
                     onChange={(e) => {
@@ -422,39 +422,39 @@ function MedicineTrackPage() {
                         setDosage(0);
                       }
                     }}
-                    label="Unit"
+                    label={t('health.unit')}
                   >
-                    <MenuItem value="ml">ml</MenuItem>
-                    <MenuItem value="mg">mg</MenuItem>
-                    <MenuItem value="tsp">tsp</MenuItem>
-                    <MenuItem value="tbsp">tbsp</MenuItem>
-                    <MenuItem value="drops">drops</MenuItem>
-                    <MenuItem value="tablet">tablet(s)</MenuItem>
+                    <MenuItem value="ml">{t('health.units.ml')}</MenuItem>
+                    <MenuItem value="mg">{t('health.units.mg')}</MenuItem>
+                    <MenuItem value="tsp">{t('health.units.tsp')}</MenuItem>
+                    <MenuItem value="tbsp">{t('health.units.tbsp')}</MenuItem>
+                    <MenuItem value="drops">{t('health.units.drops')}</MenuItem>
+                    <MenuItem value="tablet">{t('health.units.tablet')}</MenuItem>
                   </Select>
                 </FormControl>
               </Box>
 
               <FormControl fullWidth sx={{ mb: 3 }}>
-                <InputLabel>Route</InputLabel>
+                <InputLabel>{t('health.route.label')}</InputLabel>
                 <Select
                   value={route}
                   onChange={(e) => setRoute(e.target.value as 'oral' | 'topical' | 'injection' | 'other')}
-                  label="Route"
+                  label={t('health.route.label')}
                 >
-                  <MenuItem value="oral">Oral</MenuItem>
-                  <MenuItem value="topical">Topical</MenuItem>
-                  <MenuItem value="injection">Injection</MenuItem>
-                  <MenuItem value="other">Other</MenuItem>
+                  <MenuItem value="oral">{t('health.route.oral')}</MenuItem>
+                  <MenuItem value="topical">{t('health.route.topical')}</MenuItem>
+                  <MenuItem value="injection">{t('health.route.injection')}</MenuItem>
+                  <MenuItem value="other">{t('health.route.other')}</MenuItem>
                 </Select>
               </FormControl>
 
               <TextField
                 fullWidth
-                label="Reason (optional)"
+                label={t('health.reason.label')}
                 value={reason}
                 onChange={(e) => setReason(e.target.value)}
                 sx={{ mb: 3 }}
-                placeholder="e.g., Fever, Pain, Allergy"
+                placeholder={t('health.reason.placeholder')}
               />
 
               <TextField
@@ -477,7 +477,7 @@ function MedicineTrackPage() {
                 onClick={handleSubmit}
                 disabled={loading}
               >
-                {loading ? t('activities.medicine') : t('activities.medicine')}
+                {loading ? t('common.loading') : t('health.logMedicine')}
               </Button>
             </Paper>
 
@@ -485,7 +485,7 @@ function MedicineTrackPage() {
             <Paper sx={{ p: 3 }}>
               <Box sx={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', mb: 2 }}>
                 <Typography variant="h6" fontWeight="600">
-                  {t('activities.medicine')}
+                  {t('health.recentMedicines')}
                 </Typography>
                 <IconButton onClick={loadRecentMedicines} disabled={medicinesLoading}>
                   <Refresh />
@@ -578,10 +578,10 @@ function MedicineTrackPage() {
           </DialogContent>
           <DialogActions>
             <Button onClick={() => setDeleteDialogOpen(false)} disabled={loading}>
-              Cancel
+              {t('common.cancel')}
             </Button>
             <Button onClick={handleDeleteConfirm} color="error" disabled={loading}>
-              {loading ? t('deleteEntry') : t('deleteEntry')}
+              {loading ? t('common.loading') : t('common.delete')}
             </Button>
           </DialogActions>
         </Dialog>