feat: support post scaffold hooks

[hay-kot]

Notable Changes from Original PR

• Uses settings pattern similar to the new theme config.
• Moves flag to base command similar the other settings overrides
• Moves some files around
• Supports prefix style matches so hooks can have extensions
• Adds a bit more documentation
• Changes default to prompt

Also See

• feat: hooks #154

[hay-kot]

@izeau - I made some changes on top of your PR. Mostly just preference/style things. Let me know if you have any thoughts!

[izeau]

Well that's really great - and a bit humbling if I'm being honest. I'm thankful that you took the time to review and improve this, and sorry you had to rework it that much!

[hay-kot]

and a bit humbling if I'm being honest

I wouldn't feel too bad. Really the only thing I changed that wasn't a 'same thing but my way' kind of change was the matching prefixes thing. everything else you wrote was perfectly fine!