Fix infinite loop: replace OJS reactivity with imperative DOM updates

The side panel was causing a reactive cycle:
  globeStatus change → sidePanel re-render → layout re-render →
  viewer re-create → phase1 re-run → globeStatus change → loop

Fix: all side panel content is static HTML. Stats, cluster card,
and sample list are updated via getElementById/innerHTML only.
No OJS mutable variables, no reactive cascade.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: rdhyee