The game tab held a "Press Play" hint where the picture belongs. It now previews the scene through the active camera, and says "No active camera" when none is switched on. Camera choice and its world position moved into activeCamera.ts so both are testable without Pixi. Entity.x/.y are parent-relative; the viewport used them as the camera's spot, which framed a parented camera at the wrong place.
todo-notes
A drop box for ideas that come up while work is already in progress, so they are not lost and not squeezed into the running task. One file per topic, free form, any language.
Anything in here is fair game to pick up at any time. When a note is done, move the file to done/
rather than deleting it – the note says what was wanted, the commit says what was built.