When the disc VM jumps (menu activation, end of title), the demuxer
and player have to flush and reinitialize exactly at the boundary.
Hold an EOF at the boundary until the demuxer acks it, and resync
the player with a regular seek, which already orders flush, decoder
reset and restart. d_seek recognizes the held boundary and releases
it instead of repositioning the VM.
Also log the VM domain in nav event messages.