feat: Convertir módulo de clases para usar TenantCRUDRoutes

Cambios en backend:
- Actualizado ClassResponseDTO con campos de tenant y timestamps
- Agregados métodos estáticos en servicio (get_all, get_by_id, create, update, delete)
- Reemplazados endpoints de rutas con inicialización de TenantCRUDRoutes
- Corregida ruta de importación del modelo Company en security.py
- Actualizados nombres de campos en DTO para coincidir con modelo (description_es/en)
- Agregada validación para constraint de foreign key de material_key
- Agregada validación de class_code duplicado en método create
- Agregado TimestampMixin al modelo Class
- Creada migración de Alembic para agregar columnas timestamp a tabla classes
- Corregido orden de parámetros en firma del método update

Cambios en frontend:
- Actualizados componentes de UI para módulo de clases

backend/api/v1/modules/a76/classes/dto.py

@@ -3,9 +3,10 @@ DTOs (Data Transfer Objects) para módulo de clases SCAII y SCAF
 Reemplaza schemas.py siguiendo enfoque DDD y estilo NestJS
 """
 
+from datetime import datetime
 from typing import Optional
 
-from pydantic import BaseModel, Field
+from pydantic import BaseModel, ConfigDict, Field
 
 
 class ClassCreateDTO(BaseModel):
@@ -13,10 +14,10 @@ class ClassCreateDTO(BaseModel):
 
     client_id: int = Field(..., description="Client key")
     class_code: str = Field(..., max_length=8, description="Class code")
-    description_spanish: Optional[str] = Field(
+    description_es: Optional[str] = Field(
         None, max_length=500, description="Description in Spanish"
     )
-    description_english: Optional[str] = Field(
+    description_en: Optional[str] = Field(
         None, max_length=500, description="Description in English"
     )
     material_key: Optional[str] = Field(
@@ -50,10 +51,10 @@ class ClassCreateDTO(BaseModel):
 class ClassUpdateDTO(BaseModel):
     """DTO para actualizar una clase"""
 
-    description_spanish: Optional[str] = Field(
+    description_es: Optional[str] = Field(
         None, max_length=500, description="Description in Spanish"
     )
-    description_english: Optional[str] = Field(
+    description_en: Optional[str] = Field(
         None, max_length=500, description="Description in English"
     )
     material_key: Optional[str] = Field(
@@ -87,10 +88,13 @@ class ClassUpdateDTO(BaseModel):
 class ClassResponseDTO(BaseModel):
     """DTO para respuesta de clase"""
 
+    id: int
+    tenant_id: int
+    company_id: int
     client_id: int
     class_code: str
-    description_spanish: Optional[str] = None
-    description_english: Optional[str] = None
+    description_es: Optional[str] = None
+    description_en: Optional[str] = None
     material_key: Optional[str] = None
     unit_of_measure: Optional[str] = None
     fraction: Optional[str] = None
@@ -98,9 +102,10 @@ class ClassResponseDTO(BaseModel):
     sub_key: Optional[str] = None
     physical_review: Optional[int] = None
     iva_exempt_fraction: Optional[str] = None
+    created_at: datetime
+    updated_at: datetime
 
-    class Config:
-        from_attributes = True
+    model_config = ConfigDict(from_attributes=True)
 
 
 class ClassBasicDTO(BaseModel):
@@ -108,8 +113,8 @@ class ClassBasicDTO(BaseModel):
 
     client_id: int
     class_code: str
-    description_spanish: Optional[str] = None
-    description_english: Optional[str] = None
+    description_es: Optional[str] = None
+    description_en: Optional[str] = None
     material_key: Optional[str] = None
     fraction: Optional[str] = None