feat: Implement invoice management module with CRUD operations

- Added InvoiceHeader, InvoiceComplianceMx, InvoiceFinancials, InvoiceLogistics, InvoiceSalesDetails, and InvoiceCollections models.
- Created schemas for invoice operations including create, update, and response schemas.
- Developed services for handling business logic related to invoices, including retrieval, creation, updating, and deletion of invoices and their related data.
- Introduced routes for invoice management, enabling CRUD operations through a RESTful API.
- Integrated invoice routes into the main application router.
- Removed unused routers from the core module to streamline the API structure.

backend/api/v1/modules/core/router.py

@@ -0,0 +1,12 @@
+from .auth.routes import router as auth_router
+from .licenses.routes import router as licenses_router
+from .tenants.routes import router as tenants_router
+from .user_tenant.routes import router as user_tenant_router
+from fastapi import APIRouter
+
+router = APIRouter()
+
+router.include_router(auth_router)
+router.include_router(tenants_router, prefix="/core", tags=["core / tenants"])
+router.include_router(user_tenant_router, prefix="/core", tags=["core / user-tenants"])
+router.include_router(licenses_router, prefix="/core", tags=["core / licenses"])