chore: commit FailPoint #9 changes from prior session

chore: enforce changelog updates every sprint in agent definitions

v4.2.0: Session documentation and FailPoints logging

Add session documentation — session log and team restructure decision record

v4.1.0: Close process gaps — failure loops, release authority, sprint completion

v4.0.0: Complete team restructure — 9 agent definitions

v3.3.2: Add FailPoint #8 — stale project instructions caused repeated failure

v3.3.1: Add deployment verification to Implementer and Validator (FailPoint #7)

v3.3.0: Automate GitHub setup in /new-project, add GithubTooling doc

v3.1.0: GitHub-native sprint workflow integration

v3.0.0: Unified Claude subagent architecture

v2.0.0: Add QA Agent for browser-based E2E testing

v1.4.0: Document branch strategy and multi-team parallelism TODO

v1.3.0: Application and version spec templates, release workflow skills

v1.2.0: Bump BA agent version to 1.2.0 to match project tag