fix(config): fsync backup and rename metadata

Co-Authored-By: Paperclip <noreply@paperclip.ing>

server/src/__tests__/worktree-config.test.ts

@@ -1,3 +1,4 @@
+import fsSync from "node:fs";
 import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
@@ -1029,8 +1030,13 @@ describe("worktree config repair", () => {
     delete process.env.PORT;
     delete process.env.DATABASE_URL;
 
+    const open = vi.spyOn(fsSync, "openSync");
+    const sync = vi.spyOn(fsSync, "fsyncSync");
     maybePersistWorktreeRuntimePorts({ serverPort: 3103, databasePort: 54335 });
 
+    expect(open).toHaveBeenCalledWith(paperclipDir, "r");
+    expect(sync).toHaveBeenCalled();
+
     const writtenConfig = JSON.parse(await fs.readFile(configPath, "utf8"));
     expect(writtenConfig).toMatchObject({
       topLevelExtension: { enabled: true },

server/src/worktree-config.ts

@@ -324,6 +324,21 @@ function atomicWriteFile(filePath: string, contents: string): void {
       fs.closeSync(fileDescriptor);
       fileDescriptor = null;
       fs.renameSync(temporaryPath, filePath);
+      let directoryDescriptor: number | null = null;
+      try {
+        directoryDescriptor = fs.openSync(path.dirname(filePath), "r");
+        fs.fsyncSync(directoryDescriptor);
+      } catch (error) {
+        const code = error instanceof Error && "code" in error ? error.code : null;
+        if (
+          process.platform !== "win32" ||
+          !["EACCES", "EINVAL", "EISDIR", "ENOTSUP", "EPERM"].includes(String(code))
+        ) {
+          throw error;
+        }
+      } finally {
+        if (directoryDescriptor !== null) fs.closeSync(directoryDescriptor);
+      }
       return;
     } catch (error) {
       if (fileDescriptor !== null) fs.closeSync(fileDescriptor);