feat(view): move all 3D info panels to the left stack (부재 표시, 시점, 색 기준, 원점)

The right stack is gone. 색 기준 and the ⓘ origin note now sit under 시점 in the left stack, so every 3D info panel is on the
left. The stack is 180 px wide; the origin note opens to the right of its button.

Co-Authored-By: Claude Haiku 5.5 <noreply@anthropic.com>

index.html

@@ -85,8 +85,6 @@
               <button id="views-toggle" class="btn views-toggle" type="button" aria-haspopup="true" aria-expanded="false" aria-controls="views">시점</button>
               <div id="views" class="views views-list" role="group" aria-label="시점" hidden></div>
             </div>
-          </div>
-          <div class="viewer-stack viewer-stack-right">
             <details class="info-panel color-info" id="color-info" hidden>
               <summary>색 기준 <span id="color-state" class="panel-state"></span></summary>
               <div class="rebar-color" id="rebar-color" role="group" aria-label="철근 색 기준">