Transform of salvaged PR #34250 per maintainer direction: arbitrary
config keys are a supported pattern (top-level scalars bridge into
os.environ for skills and external apps), so hard-refusing unknown
keys would break legitimate writes. Keep the contributor's schema
walker and did-you-mean suggestion engine, but write the value first
and print a post-write notice — no more bare success for
plausible-but-wrong paths like
gateway.discord.gateway_restart_notification, and no blocked writes.
--force suppresses the notice for scripted use.
ed3a0b3948