Persist project settings updates

src/frontend/utils/api.ts

@@ -15,6 +15,7 @@ import type {
   ProjectRevisionPageDto,
   ProjectSnapshotMetadataDto,
   ProjectSnapshotRestoreResultDto,
+  ProjectSettingsCommandResultDto,
   ProjectDeviceSyncCommandResultDto,
   ProjectDeviceSyncPreviewDto,
   ProjectDto,
@@ -205,12 +206,16 @@ export function createProject(name: string) {
 
 export function updateProjectSettings(
   projectId: string,
+  expectedRevision: number,
   input: { singlePhaseVoltageV: number; threePhaseVoltageV: number }
 ) {
-  return request<ProjectDto>(`/api/projects/${projectId}`, {
+  return request<ProjectSettingsCommandResultDto>(
+    `/api/projects/${projectId}`,
+    {
     method: "PUT",
-    body: JSON.stringify(input),
-  });
+      body: JSON.stringify({ expectedRevision, ...input }),
+    }
+  );
 }
 
 export function listDistributionBoards(projectId: string) {