Bugbot is now over 3x faster, 22% cheaper, and finds 10% more bugs

This post details significant performance improvements to Bugbot, making it over 3x faster, 22% cheaper, and capable of finding 10% more bugs per review. These gains are attributed to harness improvements and progress in training Composer 2.5, which now powers Bugbot. New user-facing features include the ability to run Bugbot and Security Review with `/review` before pushing code, and a configuration option to "Only review what's new in your PR" to avoid re-reviewing previously approved code.