v0.19.0

See CHANGELOG.md for the full release notes.

What's Changed

• Benchmark tables are gated against stale artifacts, re-recorded on 0.18.0 with same-shape rows, and throughput is stated as the comparison it is by @codetalcott in #243
• The --blocking-threads handoff rides in-memory rings; the socketpairs carry only wakes and payloads by @codetalcott in #245
• The loop thread's header path costs what tokio's does by @codetalcott in #246
• The loop-user-space note prices its own next step, and says to stop by @codetalcott in #247
• The zero-config pool serves a trivial view at the one-thread rate: one idle spinner, no wake while a thread is busy, a wake by name to the thread that parked last, and the loop waking a sibling only for a ring nobody drains by @codetalcott in #248
• The pool's fast-route tail was the keep-alive request cap: default 1000, a flag and env var for it, and the instruments that placed it by @codetalcott in #252
• The pool's instruments are in the tree: scripts/probes/, poe stress-pool (SPEC E18), and a check-docs rule against citing untracked paths by @codetalcott in #251
• The benches refuse to lie about their own variance: quiet-machine gate, p99 spread with a three-round floor, comparator-drift refusal by @codetalcott in #250
• Release 0.19.0 by @codetalcott in #254

Full Changelog: v0.18.0...v0.19.0