Layout: replace admin-container wrapper with #builder-page flex column;
add min-height:0 to builder-wrap, builder-body, both panels so the
inner scroll areas actually shrink correctly in a flex column.
Loading...: scripts at end of body mean DOMContentLoaded may have
already fired by the time the listener is registered. Check
document.readyState first and call init() directly if DOM is ready.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
pguzman
b894e22bdc