refactor(host/W6.2): extract the video encode backends into the pf-encode crate

encode.rs + encode/* (NVENC, VAAPI, native AMF, AMF/QSV ffmpeg, direct-SDK
NVENC/CUDA, raw Vulkan-Video, PyroWave, openh264) move into crates/pf-encode
behind one Encoder trait + open_video selector (plan §W6). The crate speaks the
shared frame vocabulary (pf-frame: CapturedFrame/PixelFormat + the DXGI identity
D3d11Frame/make_device) and pf-zerocopy (CUDA context/buffers), and NEVER
pf-capture — the capture→encode edge is one-way (ZeroCopyPolicy, prior commit).

Dep moves: the heavy encoder deps (ffmpeg-next, the NVENC SDK, openh264,
pyrowave-sys) move from the host to pf-encode; the host's
nvenc/amf-qsv/vulkan-encode/pyrowave features now FORWARD to pf-encode/*. The
host keeps a mod-encode shim (pub use pf_encode) so every crate::encode::* path
(negotiator + GameStream/native/mgmt planes) is unchanged.

resolve_render_adapter_luid moves from the host's windows/win_adapter.rs into
pf-gpu (both pf-encode and pf-capture need it as a peer of GPU selection); its 5
call sites (encode amf/nvenc, capture idd_push/synthetic_nv12, vdisplay manager)
rewire to pf_gpu::resolve_render_adapter_luid and win_adapter.rs is deleted.
pf-frame's make_device gains a # Safety section (public-unsafe-fn lint, latent
since the pf-frame carve — a full-workspace -D warnings clippy catches it).

Verified: Linux clippy -D warnings (pf-encode + host nvenc,vulkan-encode,pyrowave
--all-targets) + 13/13 pf-encode + 299/299 host tests; Windows clippy -D warnings
(pf-encode nvenc,amf-qsv --all-targets + host nvenc,amf-qsv --all-targets)
Finished exit 0.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

crates/punktfunk-host/src/windows/win_adapter.rs

@@ -1,44 +0,0 @@
-//! Backend-neutral DXGI adapter selection.
-//!
-//! The discrete render-GPU LUID picker used to live in the SudoVDA backend (`vdisplay::sudovda`) — a
-//! historical accident, since it is display-utility, not SudoVDA-specific. It lives here so the capturers
-//! (IDD-push) and the pf-vdisplay backend depend on it as a *peer* instead of reaching into the SudoVDA
-//! module — breaking that circular reach-in, which let the SudoVDA backend be dropped without losing this
-//! helper (audit §9 / Goal 2 — done). This is the plan's `windows/adapter.rs`.
-//!
-//! The selection logic itself now lives in [`crate::gpu`] (shared with the mgmt API's GPU
-//! endpoints): **operator preference (web console) > `PUNKTFUNK_RENDER_ADAPTER` substring > max
-//! `DedicatedVideoMemory`**, WARP/Basic-Render and indirect-display ghost twins always excluded.
-//! This wrapper is the LUID-shaped view of it, plus the per-decision logging (call sites are
-//! per-session, never per-frame).
-
-use windows::Win32::Foundation::LUID;
-
-/// Pick the render GPU LUID the pipeline is created on: the IDD-push capturer's shared-texture
-/// ring, the IddCx SET_RENDER_ADAPTER pin, and (via the captured frame's device) NVENC/AMF/QSV all
-/// follow this one decision — see [`pf_gpu::selected_gpu`] for the precedence. A configured
-/// preference that doesn't match a present GPU falls back to auto selection (with a warning)
-/// rather than returning `None`, so a stale preference never stops the host from streaming.
-pub(crate) fn resolve_render_adapter_luid() -> Option<LUID> {
-    match pf_gpu::selected_gpu() {
-        Some(sel) => {
-            tracing::info!(
-                adapter = sel.info.name,
-                vram_mb = sel.info.vram_bytes / (1024 * 1024),
-                source = sel.source.tag(),
-                "render adapter selected"
-            );
-            if sel.source == pf_gpu::PickSource::PreferenceMissing {
-                tracing::warn!(
-                    "the preferred GPU is not present — auto-selected the adapter above \
-                     (fix or clear the preference in the web console)"
-                );
-            }
-            Some(sel.info.luid())
-        }
-        None => {
-            tracing::warn!("no suitable render adapter found for SET_RENDER_ADAPTER");
-            None
-        }
-    }
-}