[feature] persist worker queues to db

[NyaaaWhatsUpDoc]

Description

Persists the state of worker queues to the database on shutdown, and attempts to recover them from database on startup.

Before this is reviewed (or even has a readable diff), it depends on both #3000 and #2989.

This replaces #3019 as frankly trying to rebase that thing was horrible, it was easier to just cherry-pick the stream of commits ontop of main.

Checklist

• I/we have read the GoToSocial contribution guidelines.
• I/we have discussed the proposed changes already, either in an issue on the repository, or in the Matrix chat.
• I/we have not leveraged AI to create the proposed changes.
• I/we have performed a self-review of added code.
• I/we have written code that is legible and maintainable by others.
• I/we have commented the added code, particularly in hard-to-understand areas.
• I/we have made any necessary changes to documentation.
• I/we have added tests that cover new code.
• I/we have run tests and they pass locally with the changes.
• I/we have run go fmt ./... and golangci-lint run.

[tsmethurst]

Nice one :)