Change the matplotlib figure size from (10, 4) to (10, 6) so the
star history chart renders vertically longer in the README. The
regenerated note/star_history.svg reflects the new 5:3 aspect ratio
(720x432pt) instead of the previous flat 2.5:1 (720x288pt).
* docs(readme): replace star-history.com with self-generated chart
The star-history.com SVG is a third-party dependency that can rate
limit or go down. Replace it with a GitHub Action that fetches
stargazers via the REST API and renders an SVG with matplotlib,
committing note/star_history.svg weekly. The README references the
committed file directly, so the chart has no runtime dependency on
any external service.
* ci(star-history): run daily instead of weekly