Add missing move() with cross-device fallback (rename → copy+rm on
EXDEV), needed by OfficialModules.createModuleDirectories for directory
migrations during upgrades.
Honor overwrite/errorOnExist options in copy() to match fs-extra
behavior for callers that pass these flags.
fs-extra routes all operations through graceful-fs, which globally
monkey-patches node:fs with a deferred retry queue. During multi-module
installs (~500+ file ops), retried unlink operations from one module's
remove phase can fire after the next module's copy phase has written
files, silently deleting them non-deterministically.
Replace fs-extra with a thin fs-native.js wrapper over node:fs/promises
and node:fs. All 21 consumers now use native APIs with no global
monkey-patching, eliminating the retry-queue race condition entirely.
Closes#1779
Brian Madison