feat: ✨ set up ACLs and migration user

[ecxyzzy]

Closes #87.

[MinhxNguyen7]

Code looks fine, but we're still getting permission denied when trying to access/write to the DB.

You can reproduce this by clicking Login, then Sign Up, then signing up with some random credentials. If the error changes to something other than a permission error, it's probably working.

Thanks for the help.

[ecxyzzy]

Yeah sorry I think I messed up the sequencing when applying the ACLs so I had to explicitly grant all permissions through psql. To make sure I dropped the existing dev schema and reran migrate, and the permissions are correct now (as verified through the CLI and by testing on the staging build).

[MinhxNguyen7]

Looks fine. Seems to work.

For the sake of moving faster, this should be merged, but, at some point, can you write in the file or readme what to do/what you did with the SQL file with all the grants?