Remove AGENTS.md, .claude/skills and .agents/skills from the repository. They
are local tooling: bash framework/scripts/install-skills.sh recreates the skill
copies, and each clone keeps all three out of git through .git/info/exclude.
The files stay in the history of main; this commit only stops tracking them.
Mount the framework as a submodule at framework/ (v0.4.0), add AGENTS.md and
the installed skill copies for Codex CLI (.agents/skills) and Claude Code
(.claude/skills).
Tirsvad