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.

frontend/src/lib/auth.ts

@@ -173,8 +173,11 @@ export const initKeycloak = async (): Promise<boolean> => {
 	}
 };
 
+// Variable para rastrear el tenant anterior
+let previousTenantId: number | undefined = undefined;
+
 /**
- * Actualiza el estado de autenticación
+ * Actualiza el estado de autenticación con los datos de Keycloak
  */
 const updateAuthState = async () => {
 	if (!keycloakInstance?.authenticated) {
@@ -189,19 +192,36 @@ const updateAuthState = async () => {
 
 		const roles = tokenParsed?.realm_access?.roles || [];
 		const tenantId = tokenParsed?.tenant_id || tokenParsed?.attributes?.tenant_id;
+		const newTenantId = tenantId ? parseInt(tenantId) : undefined;
+
+		// Detectar si cambió el tenant
+		const tenantChanged = previousTenantId !== undefined && previousTenantId !== newTenantId;
 
 		const user: User = {
 			id: profile.id || '',
 			username: profile.username || '',
 			email: profile.email,
 			name: `${profile.firstName || ''} ${profile.lastName || ''}`.trim(),
-			tenantId: tenantId ? parseInt(tenantId) : undefined,
+			tenantId: newTenantId,
 			roles
 		};
 
 		authStore.setAuthenticated(true);
 		authStore.setUser(user);
 		authStore.setToken(token);
+
+		// Si cambió el tenant, limpiar el store de compañías
+		if (tenantChanged && browser) {
+			try {
+				const { companyStore } = await import('./stores/company.svelte');
+				companyStore.clear();
+			} catch (error) {
+				console.error('Error al limpiar store de compañías:', error);
+			}
+		}
+
+		// Actualizar el tenant anterior
+		previousTenantId = newTenantId;
 	} catch (error) {
 		console.error('Error actualizando estado de autenticación:', error);
 		authStore.reset();
@@ -361,6 +381,14 @@ export const logout = async () => {
 			}
 		}
 		
+		// Limpiar store de compañías
+		try {
+			const { companyStore } = await import('./stores/company.svelte');
+			companyStore.clear();
+		} catch (error) {
+			console.error('Error al limpiar store de compañías:', error);
+		}
+		
 		// Limpiar estado local
 		authStore.reset();
 		localStorage.removeItem('access_token');