bundle: optional multithreaded compression, ATM zstd-only Compression type can be a huge chunk of "hg bundle", especially when using the higher compression levels. With level=22 and threads=7, the NetBSD test repository took 28:39 wall time and 157:47 user time. Before, level=22 would take 129:20 wall time and 129:07 user time. Differential Revision: https://phab.mercurial-scm.org/D9283

rust: Preallocate the returned `Vec` in `utils::files::relativize_path` Profiling `rhg files > /dev/null` on an old snapshot of mozilla-central (with `perf` and the Firefox Profiler: https://github.com/firefox-devtools/profiler/blob/main/docs-user/guide-perf-profiling.md) showed non-trivial time spend in this function and in `realloc`. This change makes the wall-clock time for that process on my machine go from ~190 ms to ~150 ms. Differential Revision: https://phab.mercurial-scm.org/D10199

black: merge config into main pyproject.toml now that we have it This means that naive contributors who just run `black` on a source file will get reasonable behavior as long as they have a recent black. Yay! This was previously D9834 but was rolled back due to test failures. nbjoerg thinks it's time to try again, so let's give it a shot. Differential Revision: https://phab.mercurial-scm.org/D10185

pyproject: add config file This will tell pip et al to call our setup.py for the majority of packaging concerns, but also gives us a place to put standard config stuff like black. This was previously D9833, but was rolled back due to test breakage. nbjoerg thinks that breakage is now resolved, so we're trying again. Differential Revision: https://phab.mercurial-scm.org/D10184