add bug resolution strategy

This change adds a new "Bug Resolution Strategy" section to the engineering handbook that establishes a systematic approach for managing software bugs. The new process introduces "bug burn-down cycles" - focused periods where teams prioritize fixing existing bugs when they accumulate too much technical debt.

The strategy defines clear rules for when teams must enter these intensive bug-fixing periods (like having 2+ bugs that miss performance targets) and what they must accomplish to exit (such as fixing all critical bugs and assigning remaining ones to specific release schedules). It also sets expectations for ongoing bug management, requiring teams to immediately assign new bugs to planned releases rather than letting them pile up in a backlog.

This creates a more structured and proactive approach to maintaining software quality, ensuring teams address bugs before they become overwhelming while maintaining predictable work capacity.