stage-chapters Generates a Stage chapter run for the current local git branch and opens it in a browser. Uses to compute the diff, then generates chapters and a prologue, and hands the result to to launch the SPA. Prerequisites Run these checks before any other work. If either fails, stop with the error message — do not continue. 1. is installed. Run . If it exits non-zero, instruct the user: Stop. 2. The current directory is a git repo. Run . If it does not print , stop with: Step 1 — Run prep auto-detects the base ref (main/master), computes the merge-base, generates the diff, filters out l…