Trim AGENTS.md to whole-repo, every-session facts (154 -> 110 lines) and move
subsystem guidance into docs/guides/*.md, each with paths: frontmatter and a
one-line index entry in AGENTS.md. Symlink each guide from .claude/rules/ so
Claude Code lazy-loads it by matching path; track those symlinks via a
.gitignore exception (.claude/settings.local.json stays ignored).
Agent-onboarding doc for the workspace: stack, build/test/run commands,
directory layout, conventions, and always/never gotchas, plus a Current
state section. CLAUDE.md symlinks to AGENTS.md so Claude Code auto-loads
it. Longer-term backlog lives in ROADMAP.md.