Make Comet even friendlier to agentic development

### What is the problem the feature request solves?

This is an item that I am currently working on, but wanted an issue to link to from PRs, and also to share the thinking behind this work.

Comet already has some skills in the repo for implementing and auditing expressions, and reviewing PRs. The PR review skill is quite specific to expressions.

I would like to improve the skills, and the contributor guide, to cover more areas so that we can improve the quality of reviews.

Some examples:

- Look for code duplicating existing arrow/datafusion kernels
- Review code from a performance point-of-view i.e. are we using arrow as efficiently as possible and avoiding per-row/per-element builder loops
- Have specialist knowledge of more areas of the code base, such as shuffle implementation, and memory management

I plan on creating PRs to enhance the contributor guide and will then create PRs to add/update skills to leverage that information during reviews

### Describe the potential solution

_No response_

### Additional context

_No response_