[thekevinbot]

Fixes #1461

Two changes for wide directories (hundreds of thousands of entries):

• Leaves are made on the judging threads. explore used to build each file's leaf, which is its path-table row, serially after judge_all returned. It now builds it inside the judging closure, so in a directory of at least PARALLEL_ENTRIES entries row-building runs on every core. Taken is generic over what a file carries: a path, or the leaf made of it. PR perf: build path-table rows on the walk threads #1510 moved row-building into explore, but serially per directory, so this part was still open.
• Linux reads entries with rustix::fs::RawDir. It reads into a thread-local 1 MiB buffer, so a 2M-entry directory takes few getdents calls and needs no CString per name. Other Unix systems keep Dir, and Windows keeps std::fs::read_dir. Both are unchanged.

Output is byte-identical: same md5 for path, basename, dir over ./*, ./ and ./docs on a 1.6M-item tree.

Timings

These ran on the glob_speed_one_level tree (1.6M items per level). Other agents were running at the same time, load 5 to 18.

Direct A/B, 11 interleaved runs each, median after/before:

glob	after/before
./*	0.882
./	0.887
./docs	0.840

On the 2M flat corpus, ./* went from 0.923s to 0.834s (0.904x). A deep tree (20k dirs × 10 files, ./**/*.md) was neutral at 1.02x, within noise.

The paired harness ran the .//./docs cases from #1471, untracked and not committed. Before and after ran on the same tree, two rounds each, and ratios are against the fastest native. Load made these noisy:

glob	before	after
./*	1.03 (fd), 1.28 (rg)	0.99 (fd), 0.82 (rg)
./docs	1.48, 1.65 (rg)	1.30 (rg), 1.10 (fd)
./	0.61, 0.83 (fd)	0.66, 1.05 (rg)

This PR does not restore the #1471 cases. Getting ./ and ./docs reliably to 1.0x needs the wide-directory redesign: judging, sorting and moves hidden behind the read.

E2E Verification

• Ran e2e suites locally for every affected SDK
• Python SDK e2e: pass (targeted)
• TypeScript SDK e2e: pass
• Rust core e2e (if applicable): pass
• packages/python/e2e-attestations/<branch>.json receipt written if packages/python changed (just e2e-attest-python)
• packages/ts/e2e-attestations/<branch>.json receipt written if packages/ts changed (just e2e-attest-ts)
• Command(s) run: uv run maturin develop --release, cargo build --release -p dirsql --features cli, testing-conventions e2e attest 'uv run python -m pytest tests/e2e/glob_speed_one_level_test.py tests/e2e/glob_speed_recursive_test.py tests/e2e/glob_speed_depth_bound_test.py tests/e2e/glob_speed_gitignore_test.py tests/e2e/glob_speed_dotfiles_test.py tests/e2e/glob_speed_matchers_test.py tests/e2e/glob_speed_node_modules_test.py tests/e2e/glob_speed_symlink_test.py tests/e2e/stat_speed_test.py tests/e2e/query_contract_test.py -q', just e2e-attest-ts, cargo test --workspace --features cli
• Result summary: python 26 passed; ts passed; cargo workspace all passed.

Changelog / Migrations

• Changelog fragment added under packages/rust/changelog.d/2026-10-15-wide-directory-listing.md
• Migration fragment with the same slug added under packages/rust/migrations.d/, every subsection but Summary _None._