update-web-assets

Update the third-party JavaScript vendored into the app for the artifact, diagram, and math WebViews (KaTeX, mermaid, marked, highlight.js, Tailwind, Babel, React). Checks what is outdated, reads each pin's rationale before proposing a bump, re-downloads from the official source, verifies the lock, and runs the gates. Ends by naming what must be checked on a device, because a broken WebView asset fails silently. Use…