v0.22.0

What's Changed

• docs: reflect new concurrency model (refactor phase 6) by @natanloterio in #9
• fs: async dispatch off the FUSE thread (refactor phase 3) by @natanloterio in #8
• fs+tools: SIGKILL escalation and slot reaper (refactor phases 4+5) by @natanloterio in #7
• fs: scope invocation buffers per (ino, sid) via fh (refactor phases 1+2) by @natanloterio in #6
• fs: invocation slot scaffolding (refactor phase 0) by @natanloterio in #5
• docs: project improvements report and concurrency refactor plan by @natanloterio in #4
• Add IMPROVEMENTS.md report by @natanloterio in #3
• chore: bump version to 0.22.0 by @natanloterio in #10

Full Changelog: v0.21.1...v0.22.0