variable arguments don't get completed after the first one

[gturi]

I found the following completion issue when using varags positional arguments. After the first argument is completed, pressing tab again does not show the completion anymore.

[tasks.add-users]
description = 'Add users'
usage = '''
arg "<users>" var=#true default="unknown"
complete "users" run="echo -e 'alice\nbob\ncharlie'"
'''
run = 'echo ${usage_users?}'

mise run add-users # tab
alice    bob      charlie

mise run add-users alice # tab
# no output (ideally here the completion should output only "bob charlie")

mise run add-users alice bob # enter
# correctly outputs "alice bob"

As pinpointed in the original discussion I reported the issue in usage repo and also I simplified the example so it will be easier to troubleshoot.