BuildPreviewController and WarshipSelectionController now take the WebGL
view in their constructor and call view.updateGhostPreview /
view.setSelectedUnits themselves instead of emitting bus events that
ClientGameRunner forwarded. Splits the old mountWebGLDebugRenderer in
two — createWebGLView builds the view up front so the renderer can wire
controllers to it, mountWebGLDebugRenderer does the per-frame plumbing
after the transformHandler exists. GhostPreviewUpdatedEvent had no
remaining consumers and is removed.
UILayer → WarshipSelectionController and StructureIconsLayer →
BuildPreviewController. These are the two real Controller implementations
(state + click handling, no rendering) — the new names + location reflect
what they actually do now that all rendering lives in WebGL passes.