fix(node/fs): promises not exporting fs constants (#21997)

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We were missing the `constants` export in the promise `fs` API which is
available in node.

```ts
import { constants, promises } from "node:fs";
import { constants as fsPromiseConstants } from "node:fs/promises";
console.log(constants === promises.constants); // logs: true
console.log(constants === fsPromiseConstants); // logs: true
```

Fixes https://github.com/denoland/deno/issues/21994

2 files changed, 2 insertions, 0 deletions

diff --git a/ext/node/polyfills/fs.ts b/ext/node/polyfills/fs.ts
index 01ac9912e..38a7a2bfb 100644
--- a/ext/node/polyfills/fs.ts
+++ b/ext/node/polyfills/fs.ts
@@ -137,6 +137,7 @@ const {
 
 const promises = {
   access: accessPromise,
+  constants,
   copyFile: copyFilePromise,
   cp: cpPromise,
   open: openPromise,
diff --git a/ext/node/polyfills/fs/promises.ts b/ext/node/polyfills/fs/promises.ts
index 15f238194..ffdb862d8 100644
--- a/ext/node/polyfills/fs/promises.ts
+++ b/ext/node/polyfills/fs/promises.ts
@@ -2,6 +2,7 @@
 import { promises as fsPromises } from "node:fs";
 
 export const access = fsPromises.access;
+export const constants = fsPromises.constants;
 export const copyFile = fsPromises.copyFile;
 export const open = fsPromises.open;
 export const opendir = fsPromises.opendir;