The `conversations` section was only reachable by editing config.yaml, which
production ignores: config is database-backed and the YAML is imported once,
when the database has not yet been seeded. `AdvancedConfigSchema` is also a
strict object, so a PUT carrying the section was rejected outright.
- Add `conversations` to the advanced config schema and payload, so it appears
in the dashboard's advanced JSON editor and survives a save.
- Apply the edited section field by field rather than replacing the objects,
and read the flags through to the live config from the account runtime, so a
save applies to a running account without a restart.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
jjbrunton
