What this fixes:
On boot, if PipeWire/Pulse starts with the sink at ~40%, LVA now pushes the sink volume to match the persisted LVA volume (0.0–1.0).
When you move the HA media_player volume slider, LVA now updates:
wpctl (PipeWire) if available
pactl (PulseAudio / PipeWire-Pulse) if available
amixer (ALSA) as a fallback
No reboot / alsactl store required — LVA simply re-applies the persisted volume at start.