residue v0.0.3

Feedback from running 0.0.2 on an agent monorepo: a user set residue.regenerable through GIT_CONFIG_COUNT/GIT_CONFIG_KEY_<n>/GIT_CONFIG_VALUE_<n>, the environment form of git -c, and residue ignored it without a word.

• Decision: residue still ignores residue.regenerable set through the environment (git -c and --config-env, which Git passes on as GIT_CONFIG_PARAMETERS; GIT_CONFIG_COUNT with its pairs; the legacy GIT_CONFIG). Every subprocess and CI step inherits the environment, so it must not widen what residue deletes. --regenerable is the explicit rule for one run, and Git config files are the deliberate rule for a repository.
• It no longer ignores them silently. When the environment sets the key, residue prints a note on stderr naming the values, and points at --regenerable and git config --add residue.regenerable. Every JSON document gains ignored_environment_rules: the ignored values, an empty list when there are none, or null when Git could not read that environment (for example GIT_CONFIG_COUNT=1 with no GIT_CONFIG_KEY_0). Git parses the variables itself, so quoting and key case follow Git. The schemas stay at v1. residue runs no extra Git process when none of the variables is set.
• Fix: 0.0.2 did not remove the legacy GIT_CONFIG variable. It makes git config read one file in place of every config file, so an inherited GIT_CONFIG replaced the repository's own rules, and a file it named with residue.regenerable = .env made a worktree holding .env a candidate. residue now removes GIT_CONFIG from its Git commands and reports the values in that file as ignored. It has no effect on other Git commands.
• GIT_CONFIG_GLOBAL, GIT_CONFIG_SYSTEM and GIT_CONFIG_NOSYSTEM are unchanged and documented: they choose which config files Git reads, and residue reads the same files as your Git. A user who relocates the global config keeps its residue.regenerable rules, as in 0.0.2. GIT_CONFIG_NOSYSTEM skips the system file.
• --help and the README say which sources count. AGENTS.md: after each release, upgrade this machine's Homebrew install.
• Linux packages on every release, for x86_64 and arm64: .deb for Debian and Ubuntu, .rpm for Fedora and RHEL, and a pacman package for Arch and Omarchy. Each is attested and listed in SHA256SUMS. v0.0.2 has them too.
• packaging/aur/PKGBUILD for the residue-bin AUR package.