BIM viewer no longer goes white when opening a BIMIT stage alongside it
Opening a BIMIT pipeline stage while the BIM viewer was already open would cause the BIM viewer to go entirely white, forcing a manual page refresh to recover it.
The root cause was that the point-cloud viewer forcibly destroyed every other 3D context on the page the moment it loaded — regardless of whether those contexts were in active use. The BIM viewer was always a casualty. This is now fixed. A shared context manager arbitrates which viewers are live at any given moment, using a priority system: the main BIM viewer and primary scan viewer hold the highest priority and stay live; lower-priority previews (such as inline tiles or DXF previews inside a BIMIT stage) are the first to yield if the browser's limit is reached. When a viewer does yield, it captures a still image of its last frame so the screen doesn't go blank — clicking the still resumes it immediately. The same logic applies in reverse: opening a BIMIT stage alongside the BIM viewer keeps the BIM viewer active and manages the stage's previews around it.