Yarn 4 Migration (#32253)

Migrates the Overleaf monorepo package manager from npm (v11) to Yarn 4 (v4.9.1) using node-modules linker mode.

GitOrigin-RevId: 50d32ab01955c15e29679eff9e9e9cfb897fab2d

.yarn/patches/multer-npm-2.1.1.patch

@@ -0,0 +1,13 @@
+diff --git a/lib/make-middleware.js b/lib/make-middleware.js
+index ee50988..de77364 100644
+--- a/lib/make-middleware.js
++++ b/lib/make-middleware.js
+@@ -164,7 +164,7 @@ function makeMiddleware (setup) {
+       if (fieldname == null) return abortWithCode('MISSING_FIELD_NAME')
+ 
+       // don't attach to the files object, if there is no file
+-      if (!filename) return fileStream.resume()
++      if (!filename) filename = 'undefined'
+ 
+       // Work around bug in Busboy (https://github.com/mscdex/busboy/issues/6)
+       if (limits && Object.prototype.hasOwnProperty.call(limits, 'fieldNameSize')) {