chore: update service imports for consistency and clarity

Author: pcrespov

services/catalog/src/simcore_service_catalog/service/catalog_services.py

@@ -703,6 +703,7 @@ async def batch_get_user_services(
 
     Raises:
         CatalogItemNotFoundError: When no services are found at all
+        ValidationError: if the ids are empty
     """
     unique_service_identifiers = _BatchIdsValidator.validate_python(ids)
 

services/web/server/src/simcore_service_webserver/catalog/_service.py

@@ -101,8 +101,8 @@ async def batch_get_my_services(
     product_name: ProductName,
     services_ids: list[tuple[ServiceKey, ServiceVersion]],
 ) -> MyServicesBatchGetResult:
+    assert len(services_ids) > 0  # nosec
     try:
-
         return await catalog_rpc.batch_get_my_services(
             get_rabbitmq_rpc_client(app),
             user_id=user_id,

services/web/server/src/simcore_service_webserver/projects/_controller/nodes_rest.py

@@ -546,28 +546,32 @@ async def get_project_services(request: web.Request) -> web.Response:
         )
     )
 
-    batch_got = await catalog_service.batch_get_my_services(
-        request.app,
-        product_name=req_ctx.product_name,
-        user_id=req_ctx.user_id,
-        services_ids=services_in_project,
-    )
+    services = []
+    missing = None
+
+    if services_in_project:
+        batch_got = await catalog_service.batch_get_my_services(
+            request.app,
+            product_name=req_ctx.product_name,
+            user_id=req_ctx.user_id,
+            services_ids=services_in_project,
+        )
+        services = [
+            NodeServiceGet.model_validate(sv, from_attributes=True)
+            for sv in batch_got.found_items
+        ]
+        missing = (
+            [
+                ServiceKeyVersion(key=k, version=v)
+                for k, v in batch_got.missing_identifiers
+            ]
+            if batch_got.missing_identifiers
+            else None
+        )
 
     return envelope_json_response(
         ProjectNodeServicesGet(
-            project_uuid=path_params.project_id,
-            services=[
-                NodeServiceGet.model_validate(sv, from_attributes=True)
-                for sv in batch_got.found_items
-            ],
-            missing=(
-                [
-                    ServiceKeyVersion(key=k, version=v)
-                    for k, v in batch_got.missing_identifiers
-                ]
-                if batch_got.missing_identifiers
-                else None
-            ),
+            project_uuid=path_params.project_id, services=services, missing=missing
         )
     )