Session pump, FFmpeg decode, PipeWire audio, SDL3 gamepads, keymap, trust
store, mDNS discovery, library client and Wake-on-LAN move verbatim from
clients/linux into crates/pf-client-core, shared with the upcoming Vulkan
session binary (punktfunk-planning: linux-client-rearchitecture.md).
The GTK client re-exports them at the crate root so every existing
crate::-path keeps resolving; its manifest drops the moved-only deps.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
