Benjamin Staneck cb36e1d594 Fix debug build paths Pages Router support entries (#93529) ...

## Summary
- Preserve Pages Router support entries during Turbopack
`--debug-build-paths` selective builds
- Include custom Pages Router `404` and `500` entries alongside `_app`,
`_document`, and `_error` when a Pages route is selected
- Add regression coverage for selected Pages routes retaining support
entries in `pages-manifest.json`

## Testing
- `RUSTC="$(rustup which --toolchain nightly-2026-06-24 rustc)" cargo
check -p next-api`
- `RUSTC="$(rustup which --toolchain nightly-2026-06-24 rustc)" pnpm
--dir packages/next-swc build-native`
- `HEADLESS=true pnpm test-start-turbo
test/production/debug-build-path/debug-build-paths.test.ts -t "single
page with pages/ prefix"`
- `HEADLESS=true pnpm test-start-turbo
test/production/debug-build-path/debug-build-paths.test.ts`

Fixes #93515

<!-- NEXT_JS_LLM_PR -->

2026-08-12 09:27:12 +02:00

..

fixtures

Fix debug build paths Pages Router support entries (#93529)

2026-08-12 09:27:12 +02:00

debug-build-paths.test.ts

Fix debug build paths Pages Router support entries (#93529)

2026-08-12 09:27:12 +02:00