dev: add small seed script

[tefkah]

Issue(s) Resolved

Setup is rough starting from scratch. To make it a lil easier, this seedscript creates a demo community if none exists.
This also makes pubpub treat kf-auth admins as superadmins.

Limitations:

• Still dependent on being a kf dev and having your sops keys registered.
• Does not create any other communities, nor any pubs.
• Unsure if schema is fully compatible. This does not run all migrations, which would be a better way to do it, except that "running all migrations" also doesn't sound like it would create the correct db state.
  • A better solution would be to make a schema only dump of the db and start from that, then configure any new migrations to auto run against it and store the migration state.
  • This is too much work

Test Plan

Screenshots (if applicable)

Optional

Notes/Context/Gotchas

Supporting Docs