storage_url refused only the outer URL's userinfo and unknown query
parameters. Userinfo inside the s3 endpoint= value, and rclone's
remote,param=value parameters in the remote name, were accepted and
then printed by info, remote info and snapshot create. Both are now
refused without echoing the value: a host name never contains "@", and
an rclone remote name never contains a comma. An s3 or rclone query
that cannot be decoded (a ";" or a bad "%" escape) is refused too,
because decoding drops that part before it can be checked. The comma
is checked before url.Parse, whose error for such a name prints part of
it. The rclone remote name case has its own error pointing at rclone
config.
Model: opus-5-5