Clean up settings / `slackblast.regions`

[evanpetzoldt]

I'm not fond of how many fields I have on slackblast.regions now... Given the Future State data layout (https://erd.dbdesigner.net/designer/schema/1711455527-f3-future-state), I'd like to explore of moving all of the region settings into a single json field.

Pros:

• No migration required for adding new features
• Aligns better with orgs Future State layout

Cons:

• No data validation with json data
• Size limitations?