Shader preset application, ambient lighting enable/restore/toggle, and
video zoom/boxfit lived as an extension reading per-attempt services
off the player State. Move them into VisualEffectsController, a plain
State-owned helper; the shader, ambient-lighting, and video-filter
services are injected as late-bound getters because all three are
re-created per playback attempt and nulled in teardown. Rebuilds keep
flowing through the single requestRebuild callback.
