The _fsForTest mutable object pattern fails on Linux Bun because test and source files get different module instances. Switch to passing fs operations as an optional parameter with defaults. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
The _fsForTest mutable object pattern fails on Linux Bun because test and source files get different module instances. Switch to passing fs operations as an optional parameter with defaults. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>