[waltuov]

Fixes #10487

The resolver caches misses as well as hits, and the dev engine only cleared it on a full build or a tsconfig change. So deleting a still imported file gave a silent Noop, and a missing file kept failing to resolve after it came back.

Now an incremental dev task clears the resolver cache when its batch has a create or delete, when a watched package.json changed, or when the previous task failed. The last case is for recovery. The failed round cached the miss, and the file can come back without a create event. For example, a file that was never imported is not watched, so after creating it the next importer edit would hit the cached miss again. Build watch mode documents the same recovery in internal-docs/watch-mode/implementation.md. The Rust fixture harness also reports a recreated file as an update.

Tests: the acceptance test in dev-watch.test.ts is no longer skipped. It fails before this change and passes after. delete_file_used step 0 is now an unresolved import error, as the issue expected, and its README is updated. internal-docs/dev-engine/implementation.md has a new §9c.

Alternatives: clearing on every task, like build watch mode, is simpler but throws the cache away on every edit. Per path invalidation needs a new oxc_resolver API.

Worth a look: the clear after a failed task, and editors that save by rename, since each such save now clears the cache.

[codspeed]

Merging this PR will not alter performance

✅ 7 untouched benchmarks
⏩ 10 skipped benchmarks¹

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_{Comparing waltuov:fix/dev-resolver-cache-create-delete (56938e7) with main (3f76b5c)}

Footnotes

1. 10 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩