[autofix.ci] apply automated fixes

Fixed issue where promises returned by node:fs/promises methods like
readFile() would fail instanceof Promise checks. The problem was that
wrapInternalPromise was creating JSInternalPromise objects instead of
proper JSPromise objects with the correct prototype chain.

Changes:
- Added new C++ wrapper function to create JSPromise from JSInternalPromise
- Updated wrapInternalPromise to use proper Promise constructor
- Added comprehensive test for instanceof checks on fs/promises methods

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

test/js/node/fs/fs-promises-instanceof.test.ts

@@ -0,0 +1,39 @@
+import { expect, test } from "bun:test";
+import { tempDirWithFiles } from "harness";
+import { mkdir, readFile, stat, writeFile } from "node:fs/promises";
+import { join } from "path";
+
+test("fs/promises methods return actual Promise instances", async () => {
+  const dir = tempDirWithFiles("fs-promises-instanceof", {
+    "test.txt": "test content",
+  });
+
+  const testFile = join(dir, "test.txt");
+
+  // Test readFile
+  const readResult = readFile(testFile);
+  expect(readResult instanceof Promise).toBe(true);
+  expect(readResult.constructor).toBe(Promise);
+  expect(Object.prototype.toString.call(readResult)).toBe("[object Promise]");
+
+  // Test writeFile
+  const writeResult = writeFile(join(dir, "write-test.txt"), "content");
+  expect(writeResult instanceof Promise).toBe(true);
+  expect(writeResult.constructor).toBe(Promise);
+
+  // Test stat
+  const statResult = stat(testFile);
+  expect(statResult instanceof Promise).toBe(true);
+  expect(statResult.constructor).toBe(Promise);
+
+  // Test mkdir
+  const mkdirResult = mkdir(join(dir, "new-dir"));
+  expect(mkdirResult instanceof Promise).toBe(true);
+  expect(mkdirResult.constructor).toBe(Promise);
+
+  // Ensure promises actually resolve correctly
+  await readResult;
+  await writeResult;
+  await statResult;
+  await mkdirResult;
+});