In #1766 I spotted a pre-existing typo in the repo. It would be good to be able to periodically run various LLM-based checks (rather than via CI) and one of them would be a grammar + spelling review.

We should make two agent skills - one for an overall codebase review (which should be invoked when the user specifically requests it across the whole codebase - otherwise only for touched files). It should reference as its only step at the moment a separate skill for doing grammar (and spelling, tone, etc.) checks