1. Fetch PR information using `gh pr view`.
2. Get the list of changed files using `gh pr diff --name-only`.
3. (If under 15 changed files) Fetch code diff using `gh pr diff`.
4. Check for `.pr-review-state.json` to determine incremental mode.
5. Analyze changes: categorize files, detect languages/frameworks, identify change categories, determine required references, and surface-level issues.
6. Output analysis results to `.pr-triage.json`.