feature: output power management (DPMS)

Apologies if I'm misunderstanding something. While the documentation recommends swayidle, there is currently no way to power off outputs via Display Power Management Signaling (DPMS) via IPC, nor via a tool like wlopm, because smithay and fht-compositor do not support `wlr-output-power-management-v1`, correct? If I'm missing a way to temporarily power off the display I would appreciate a quick hint, feel free to close or delete this issue. Thanks for your work!