Add 'setup' command to automate deploying necessary pages and templates

Change WishlistIntake.vue submission to use the new template.

The goal is to eventually have npm run setup give you a fully- functioning wishlist. This brings us a bit closer to that.

The new templates and wishlist pages are mostly dummy content for now.

XML dumps are not included but could be (to preserve attribution), but as the intention is really only for local envs, there's not really a need for this. The deploy script will refuse to ship 'dependency' templates and modules.

The redundancy of having wikitext in yet another version control system is amusing, but worth it given anyone with a MW installation can get a wishlist up and running quickly.

Also automate deployment of MediaWiki:Gadget-WishlistIntake

Bug: T362809

Bug: T363223