fix: hover navbar, soporte sin spinner, RETHUS en formulario profesional

- Navbar: hoverColor tenue por tema (azul/blanco) en vez del gris por defecto de Flutter web
- SettingsProvider: lazy:false + timeout 10s para evitar spinner gris permanente en soporte
- SupportView: muestra contenido con defaults inmediatamente sin bloquear en isLoading
- Modelo Profesional: campos rethus_code y rethus_validated
- ProfessionalFormProvider: soporte para rethus_code en copyProfesionalWith
- RequestProfessionalView: campo RETHUS opcional en formulario + fix color dropdown profesión

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

lib/models/profesional.dart

@@ -6,6 +6,8 @@ import 'package:prosapp_web_app/models/schedules_entity.dart';
 class Profesional {
   final String id;
   final String identification;
+  final String rethusCode;
+  final bool rethusValidated;
   final String address;
   final String aditionalAddress;
   final String profession;
@@ -25,6 +27,8 @@ class Profesional {
   const Profesional({
     required this.id,
     required this.identification,
+    required this.rethusCode,
+    required this.rethusValidated,
     required this.address,
     required this.aditionalAddress,
     required this.profession,
@@ -103,6 +107,8 @@ class Profesional {
     return Profesional(
       id: doc['id'] as String,
       identification: (doc['identification'] as String?) ?? '',
+      rethusCode: (doc['rethus_code'] as String?) ?? '',
+      rethusValidated: (doc['rethus_validated'] as bool?) ?? false,
       address: (doc['address'] as String?) ?? '',
       aditionalAddress: (doc['aditional_address'] as String?) ?? '',
       profession: (doc['profession'] as String?) ?? '',
@@ -124,6 +130,8 @@ class Profesional {
   Profesional copyWith({
     String? id,
     String? identification,
+    String? rethusCode,
+    bool? rethusValidated,
     String? address,
     String? aditionalAddress,
     String? profession,
@@ -143,6 +151,8 @@ class Profesional {
     return Profesional(
       id: id ?? this.id,
       identification: identification ?? this.identification,
+      rethusCode: rethusCode ?? this.rethusCode,
+      rethusValidated: rethusValidated ?? this.rethusValidated,
       address: address ?? this.address,
       aditionalAddress: aditionalAddress ?? this.aditionalAddress,
       profession: profession ?? this.profession,
@@ -167,6 +177,8 @@ class Profesional {
     return {
       'id': id,
       'identification': identification,
+      'rethus_code': rethusCode,
+      'rethus_validated': rethusValidated,
       'address': address,
       'aditional_address': aditionalAddress,
       'profession': profession,