lists.sr.ht: overhaul init files

Add default non-conflicting ports

Based off of config.ini debug-port values

Fix various user creation bugs and inconsistencies

- ensure that all users are added to their corresponding groups
- replace listssrht user with lists
- ensure that the git user creates its homedir
- ensure that adduser args are in same order across all apks

lists.sr.ht: normalize init scripts

Make local redis service optional

Add extra gunicorn args to *.init

Fix indent on lists.sr.ht openrc files

Add lists.sr.ht & its dependencies