Tabs now persist in localStorage across page navigations so opening
a new rApp adds it alongside existing tabs instead of replacing them.
Iframe shell shows a loading spinner with 12s timeout and error panel
when standalone apps are unreachable. Converts rSwag to iframe shell.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
The light theme was causing the header bar to render with a white
background, clashing with the dark-themed module content underneath.
All modules and both shell renderers now default to dark theme.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>