Reproduction link or steps

Reproduction: https://bolt.new/~/github-v69gmpbw

Steps to reproduce manually:

1. Create a configuration file with two objects, where one of them has an outDir option not set to dist. For example:

export default defineConfig([
  { entry: './src/index.ts' },
  { entry: './src/cli.ts', outDir: 'bin' }
])

2. Run pnpm tsdown -w
3. Change some source code in index.ts or cli.ts

What is expected?

Only one rebuild should be triggered.

What is actually happening?

The rebuild process enters an infinite loop.

Any additional comments?

Thanks a lot for this awesome tool! It's exactly what I’ve been looking for to build TS libs with minimal config. Really happy I discovered it.