Methodology for categorizing changes, assessing risks, and creating summaries from any changeset. Triggers: diff analysis, changeset review, risk assessment, change categorization, semantic analysis, release preparation, change summary, git diff Use when: analyzing specific changesets, assessing risk of changes, preparing release notes, categorizing changes by type and impact DO NOT use when: quick context catchup - use catchup instead. DO NOT use when: full PR review - use review-core with pensive skills. Use this skill for systematic change analysis with risk scoring.