Fork and Copilot related enhancements

I have three potential PRs for someone to look at based on my recent experience contributing back to this repo. Probably best to discuss in each of my PRs, since that's the easiest way for me to continue the session with Copilot. Let me know which ones you're interested in.. I'll PR them upstream or close my fork PRs.

• Skip Claude Code Review on forks unless explicitly enabled by Copilot · Pull Request #6 · alexdresko/hackgreenville-com -- The claude-review action always fails in my repo, so this seemed like the correct fix
• Add Copilot setup workflow for PHP 8.5 by Copilot · Pull Request #5 · alexdresko/hackgreenville-com - When you ask Copilot to do something, it fails to run some of the checks that are configured in the repo due to that environment not having the requisite tools. See https://docs.github.com/en/copilot/how-tos/use-copilot-agents/coding-agent/customize-the-agent-environment
• Add root AGENTS.md guidance for branch naming and conventional commits by Copilot · Pull Request #4 · alexdresko/hackgreenville-com - This is just another attempt to assist Copilot with creating valid PRs and commits against the hg repo.