feat: 6 mejoras simultáneas en prosappweb

- web/index.html: lang=es (evita traductor) + cache busting con timestamp en flutter_bootstrap.js
- profesional.dart: rate → número, location_preferences → string para coincidir con backend DTO
- location_preferences.dart: funciones locationPrefsToString/locationPrefsFromValue
- auth_provider.dart: _navigateAfterAuth redirige a setup-city si user.city vacío, método updateCity y linkEmailWithOtp
- setup_city_view.dart: nueva vista con GPS + Nominatim para detectar ciudad, campo editable, omitir
- email_view.dart: rediseño completo con flujo OTP (paso 1: email+contraseña → paso 2: código recibido en correo)
- router + dashboard_handlers: ruta /dashboard/setup-city

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

lib/models/location_preferences.dart

@@ -9,3 +9,23 @@ enum LocationPreferences { office, delivery, both }
 LocationPreferences intToEnum(int value) {
   return LocationPreferences.values[value];
 }
+
+String locationPrefsToString(LocationPreferences p) {
+  switch (p) {
+    case LocationPreferences.office: return 'office';
+    case LocationPreferences.delivery: return 'delivery';
+    case LocationPreferences.both: return 'both';
+  }
+}
+
+LocationPreferences locationPrefsFromValue(dynamic v) {
+  if (v is int) return intToEnum(v);
+  if (v is String) {
+    switch (v) {
+      case 'delivery': return LocationPreferences.delivery;
+      case 'both': return LocationPreferences.both;
+      default: return LocationPreferences.office;
+    }
+  }
+  return LocationPreferences.office;
+}

lib/models/profesional.dart

@@ -113,8 +113,8 @@ class Profesional {
       aditionalAddress: (doc['aditional_address'] as String?) ?? '',
       profession: (doc['profession'] as String?) ?? '',
       ratePreferences: (doc['rate_preferences'] as bool?) ?? false,
-      rate: (doc['rate'] as String?) ?? '',
-      locationPreferences: intToEnum((doc['location_preferences'] as int?) ?? 0),
+      rate: (doc['rate'] as num?)?.toString() ?? '',
+      locationPreferences: locationPrefsFromValue(doc['location_preferences']),
       bannerPicture: (doc['banner_picture'] as String?) ?? '',
       identificationPicture: (doc['identification_picture'] as String?) ?? '',
       certificatePicture: (doc['certificate_picture'] as String?) ?? '',
@@ -183,8 +183,8 @@ class Profesional {
       'aditional_address': aditionalAddress,
       'profession': profession,
       'rate_preferences': ratePreferences,
-      'rate': rate,
-      'location_preferences': enumToInt(locationPreferences),
+      'rate': double.tryParse(rate) ?? 0.0,
+      'location_preferences': locationPrefsToString(locationPreferences),
       'banner_picture': bannerPicture,
       'identification_picture': identificationPicture,
       'certificate_picture': certificatePicture,