Extract the list/create scope rule into sessionScopeDirectory() so loadSessions
and createSession can no longer drift apart — the root cause of #10 (sessions
empty after connect/create). Add a zero-dependency node:test regression guard
proving both paths resolve identically across all inputs, a 'test' npm script,
and exclude test files from the app typecheck.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
