The web UI sends the restore options as the form field "data". The
param helpers looked up query parameters only, so /restore never saw
them and restored the shades alone, since 3.0.0. The helpers now take a
form field too.
/restore uses an upload once, and drops the file when the options aren't
JSON.
e2e: test_restore.py, a probe that the field is read and, with --reboot,
a settings-only round trip.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
