To reproduce:

1. npm install
2. Compare outputs of:
   • npm -w app run check:ts
   • npm -w app run check:svelte
3. Should see no error in TS but in Svelte:

   File '/svelte-ts-monorepo-issue/packages/dep/index.ts' is not under 'rootDir' '/svelte-ts-monorepo-issue/packages/app'. 'rootDir' is expected to contain all source files.
     The file is in the program because:
       Imported via "dep" from file '/svelte-ts-monorepo-issue/packages/app/index.ts' with packageId 'dep/index.ts@1.0.0'
       Root file specified for compilation