findConfigFile _configPathCache temp tests

Trap: changing process.cwd() to a new temporary fixture appears to make getWorkspaceNames() discover its .craft.yml, but findConfigFile() returns the module-level _configPathCache first. A prior fixture cleanup then produces ENOENT for its deleted config, which looks like glob-resolution failure. Fix: reset discovery through the public cache-clearing path between fixture directories; do not test workspace glob behavior against a stale cached config path.