feat: Implement multi-tenancy support in middleware and security layers

- Enhanced TenantMiddleware to validate tenant information from JWT tokens.
- Added LicenseValidationMiddleware to check tenant licenses before processing requests.
- Updated security utilities to extract tenant information from tokens and validate company access.
- Introduced CompanyStore to manage active company state and handle company switching in the frontend.
- Modified API routes to include company_id in requests for better resource management.
- Improved logging and error handling throughout the middleware and API layers.
- Updated frontend components to reflect changes in company management and selection.
- Added new API route for fetching user's companies with proper authentication handling.

backend/core/database.py

@@ -3,6 +3,7 @@ Configuración de base de datos con soporte multi-tenant
 - Base de datos compartida (core_db) para tenants pequeños/medianos
 - Bases de datos dedicadas para clientes enterprise
 """
+
 from sqlalchemy import create_engine
 from sqlalchemy.orm import declarative_base
 from sqlalchemy.orm import sessionmaker, Session
@@ -20,14 +21,10 @@ core_engine = create_engine(
     pool_pre_ping=True,
     pool_size=10,
     max_overflow=20,
-    echo=settings.DEBUG
+    echo=settings.DEBUG,
 )
 
-CoreSessionLocal = sessionmaker(
-    autocommit=False,
-    autoflush=False,
-    bind=core_engine
-)
+CoreSessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=core_engine)
 
 # Engine asíncrono para operaciones async
 async_core_engine = create_async_engine(
@@ -35,13 +32,11 @@ async_core_engine = create_async_engine(
     pool_pre_ping=True,
     pool_size=10,
     max_overflow=20,
-    echo=settings.DEBUG
+    echo=settings.DEBUG,
 )
 
 AsyncCoreSessionLocal = async_sessionmaker(
-    async_core_engine,
-    class_=AsyncSession,
-    expire_on_commit=False
+    async_core_engine, class_=AsyncSession, expire_on_commit=False
 )
 
 # Cache de engines para tenants con BD dedicada
@@ -74,33 +69,32 @@ async def get_async_core_db() -> AsyncGenerator[AsyncSession, None]:
 def get_tenant_engine(tenant_id: int, db_config: dict):
     """
     Obtiene o crea un engine para un tenant con BD dedicada
-    
+
     Args:
         tenant_id: ID del tenant
         db_config: Configuración de BD {host, port, name, user, password}
-    
+
     Returns:
         Engine de SQLAlchemy para el tenant
     """
     if tenant_id not in _tenant_engines:
         db_url = f"postgresql://{db_config['user']}:{db_config['password']}@{db_config['host']}:{db_config['port']}/{db_config['name']}"
         _tenant_engines[tenant_id] = create_engine(
-            db_url,
-            pool_pre_ping=True,
-            pool_size=5,
-            max_overflow=10
+            db_url, pool_pre_ping=True, pool_size=5, max_overflow=10
         )
     return _tenant_engines[tenant_id]
 
 
 @contextmanager
-def get_tenant_db(tenant_id: int, db_config: Optional[dict] = None) -> Generator[Session, None, None]:
+def get_tenant_db(
+    tenant_id: int, db_config: Optional[dict] = None
+) -> Generator[Session, None, None]:
     """
     Context manager para obtener sesión de BD de un tenant específico
-    
+
     Si db_config es None, usa la BD core (compartida)
     Si db_config está presente, usa la BD dedicada del tenant
-    
+
     Uso:
         with get_tenant_db(tenant_id, config) as db:
             # operaciones con db
@@ -113,7 +107,7 @@ def get_tenant_db(tenant_id: int, db_config: Optional[dict] = None) -> Generator
         engine = get_tenant_engine(tenant_id, db_config)
         SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
         db = SessionLocal()
-    
+
     try:
         yield db
     finally: