v20.0.2

A maintenance release for repository tooling and contributor checks. The package behavior, the brain format (version: 8), bf.yaml, the reply schemas, the packaged skills, the assistant queue and the search cache are unchanged; no upgrade step is needed.

Changed

• Repository checks and workflow tools. Secret scanning uses Betterleaks 1.9.0 (.betterleaks.toml), workflow linting uses jactionlint 2.4.0 and zizmor 1.31.1 with $/ self-repository reusable workflow references, and dprint's Markdown plugin is updated to 0.28.0.
• Linter, hook and task hardening. pyproject.toml adds Ruff's BLE, PLE and PLW rule families and rejects blanket ty ignore comments; lefthook.yml uses sequential jobs; mise.toml enforces min_version = "2026.10.21" and UV_MALWARE_CHECK=1 on install and upgrade; and AGENTS.md and bf-contribute format rules with scannable lead-ins.