Settings changes are applied to the latest stored settings under a cross-process lock and renamed into place in one step, so two instances no longer erase each other's changes and a file that cannot be read is never replaced by defaults. Invalid content is repaired per property with a copy of the original kept aside. ADR-0006 records the file protocol. Closes #46 Co-Authored-By: Claude Fable 5.2 <noreply@anthropic.com> Signed-off-by: James Maes <james@kof22.com>