Public API Expansion & Reliability Fixes

New Features

• Introduces six new development metrics endpoints in the public API, enabling programmatic access to active contributor days, pull request activity, commit history, contributions outside work hours, issues resolution trends, and project metadata lookup.
• Adds API version lifecycle headers so consumers receive advance notice when an endpoint is deprecated or scheduled for retirement, along with links to migration guidance.

Bug Fixes

• Improves reliability by automatically throttling data queries when upstream response times increase, preventing cascading slowdowns during high-traffic periods.
• Fixes an issue where supplying an inverted date range (end date before start date) on analytics endpoints returned a server error instead of a descriptive validation message.