chore(aws-serverless): Fix local cache issues (#19081)

Most of the times `@sentry/aws-serverless:build:transpile` was failing
locally:

<img width="1146" height="398" alt="Screenshot 2026-01-29 at 12 24 00"
src="https://github.com/user-attachments/assets/a51974c4-dd7f-4701-b61f-229c59b5a284"
/>

I now had some time to investigate on it. It seems that the caching is
sometimes not working pretty nicely with yarn if you have add another
working directory. With the power of `--cache-folder` we can temporarily
give another cache folder and mitigate the problem.

In total the fix is not ideal and more of a band-aid solution. If there
are other ideas I'm fully up for it.

Author: JPeer264

packages/aws-serverless/scripts/buildLambdaLayer.ts

@@ -2,6 +2,7 @@
 import { nodeFileTrace } from '@vercel/nft';
 import * as childProcess from 'child_process';
 import * as fs from 'fs';
+import * as os from 'os';
 import * as path from 'path';
 import { version } from '../package.json';
 
@@ -23,11 +24,19 @@ async function buildLambdaLayer(): Promise<void> {
   console.log('Building Lambda layer.');
   buildPackageJson();
   console.log('Installing local @sentry/aws-serverless into build/aws/dist-serverless/nodejs.');
-  run('yarn install --prod --cwd ./build/aws/dist-serverless/nodejs');
+  // Use a temporary cache folder to avoid stale cache references to local file: packages.
+  // Yarn's global cache can contain outdated references to build artifacts from other
+  // @sentry/* packages (e.g., build/node_modules paths that no longer exist), causing
+  // ENOENT errors during file copying.
+  // The cache folder must be outside the monorepo to avoid recursive nesting when Yarn
+  // follows file: links and copies package directories.
+  const cacheFolder = path.join(os.tmpdir(), `sentry-lambda-build-cache-${Date.now()}`);
+  run(`yarn install --prod --cwd ./build/aws/dist-serverless/nodejs --cache-folder "${cacheFolder}"`);
 
   await pruneNodeModules();
   fs.rmSync('./build/aws/dist-serverless/nodejs/package.json', { force: true });
   fs.rmSync('./build/aws/dist-serverless/nodejs/yarn.lock', { force: true });
+  fs.rmSync(cacheFolder, { recursive: true, force: true });
 
   // The layer also includes `awslambda-auto.js`, a helper file which calls `Sentry.init()` and wraps the lambda
   // handler. It gets run when Node is launched inside the lambda, using the environment variable