When running /gsd:update from $HOME, the local path ./.claude/ resolves
to the same directory as $HOME/.claude/. The local branch always wins,
triggering --local reinstall that corrupts all paths in a global install.
This is self-reinforcing — once corrupted, every subsequent update
perpetuates the corruption.
Compare canonical paths (via cd + pwd) and only report LOCAL when the
resolved directories differ. When they're the same, fall through to
GLOBAL detection.
Closes#721
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>