[Request] Remove database connection dependency for model annotations

[tony-pizza]

Context: I want to run model annotations in CI (e.g. GitHub Actions). This currently requires spinning up a MySQL container service, creating our databases and loading the schemas for every annotation job run. This adds extra runner minutes and complexity.

I was honestly surprised to learn a connection was required as I'd assumed annotations were built purely from schema files.

The connection happens in ModelWrapper (see below). I'm sure there's a good reason why database introspection is used here vs inferring from schema files, but I'd like to voice that a connection-less option would be valuable.

annotaterb/lib/annotate_rb/model_annotator/model_wrapper.rb

Lines 37 to 43 in b9554dd

	def connection
	if @klass.respond_to?(:lease_connection)
	@klass.lease_connection
	else
	@klass.connection
	end
	end

Thanks!