Stable release: Supply chain security and feature graduation. Implements SBOM generation, attestation, and release upload (#455, #256) with verification docs (#454) and retention policy (#453). Adds security automation for weekly SHA staleness checks (#268) and gitleaks secret scanning as a PR gate (#260). Evaluates fuzzing integration for Scorecard compliance (#459). Extends the agent ecosystem with a Security Auditor for gap analysis (#336) and a /learn chat mode (#157). Expands skills library (#320) and updates extension packaging to distribute skills (#251).