Previously cheat only checked the current working directory for a .cheat
subdirectory. Now it walks upward through ancestor directories, stopping
at the first .cheat directory found. This mirrors how git discovers .git
directories, so users can place .cheat at their project root and have it
work from any subdirectory.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Move `doc/adr/` to `adr/` for discoverability. Remove the generic
ADR README — `ls adr/` serves the same purpose.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>