feat(pyrowave): Windows host HDR + 4:4:4, Rust client HDR present

Phase 3 of design/pyrowave-444-hdr.md. A PyroWave session now negotiates HDR
(10-bit) and 4:4:4 on a Windows host exactly like HEVC/AV1, and the Linux
client presents it through the real HDR10 path.

Host (Windows): BgraToYuvPlanes becomes mode-aware — SDR/BGRA and HDR/scRGB
variants at half- or full-res chroma. The HDR passes reuse HdrP010Converter's
exact colour math (scRGB -> PQ BT.2020 limited studio codes, verified by
hdr_p010_selftest) but write P010-style MSB-packed codes into two separate
shareable R16_UNORM/R16G16_UNORM textures; chroma keeps the pyrowave family's
centre-sited 2x2 box. idd_push pins the composition to the NEGOTIATED depth
(SDR sessions force advanced color off as before; 10-bit sessions enable it
and ride the FP16 ring), and the descriptor poller re-asserts that state
instead of following display flips the fixed-format encoder can't. The
encoder imports 8/16-bit planes per session and stamps the sequence header's
BT.2020/PQ/matrix bits on HDR (stamp_color_bits, extending 574e3e4e's range
stamp); supports_10bit/can_encode_10bit/can_encode_444 gates open (HDR
Windows-only — Linux capture has no HDR source).

Client: the plane ring becomes R16_UNORM for 10-bit sessions (with a
STORAGE_IMAGE format probe), the planar CSC pass joins the HDR10 swapchain
rebuild (set_hdr_mode previously destroyed it without rebuilding — latent),
st.hdr follows frame.color.is_pq(), and the planar push constants carry
depth-10 MSB-packed rows + the PQ tonemap mode, identical to the NV12 arm.

Verified: .173 (RTX 4090) deploy-config clippy + fmt + wire tests + the
extended pyrowave_win_smoke (10-case {SDR,HDR}x{420,444} matrix incl. R16
imports and header stamps); .21 (RTX 5070 Ti) clippy across 4 crates, host
186 tests, client/presenter/encode tests, both Linux GPU smokes.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

crates/pf-presenter/src/vk/present.rs

@@ -39,7 +39,7 @@ impl Presenter {
             #[cfg(windows)]
             FrameInput::D3d11(d) => Some(d.color.is_pq()),
             #[cfg(all(target_os = "linux", feature = "pyrowave"))]
-            FrameInput::PyroWave(f) => Some(f.color.is_pq()), // always SDR today
+            FrameInput::PyroWave(f) => Some(f.color.is_pq()),
         };
         if let Some(pq) = frame_pq {
             // A PQ stream we can only tone-map (no HDR10 surface) is the silent failure behind
@@ -750,11 +750,31 @@ impl Presenter {
                 &[planar.desc_set],
                 &[],
             );
-            let rows = csc_rows(color, 8, false);
+            // An HDR (PQ) pyrowave session carries P010-style 10-bit studio codes MSB-packed
+            // into 16-bit planes (design/pyrowave-444-hdr.md §2.2) — same sampling scale as
+            // the P010 path; SDR sessions are plain 8-bit BT.709 limited. Depth follows the
+            // colour contract (negotiation couples 10-bit ⟺ PQ for this codec).
+            let (depth, msb_packed) = if color.is_pq() {
+                (10, true)
+            } else {
+                (8, false)
+            };
+            let rows = csc_rows(color, depth, msb_packed);
+            // Mode 1 = PQ→SDR tonemap (PQ stream without an HDR10 surface); mode 0 passes
+            // the transfer through — identical to the NV12 arm above.
+            let mode = if color.is_pq() && !self.hdr_active {
+                1.0f32
+            } else {
+                0.0
+            };
+            let peak = std::env::var("PUNKTFUNK_TONEMAP_PEAK")
+                .ok()
+                .and_then(|v| v.parse::<f32>().ok())
+                .unwrap_or(4.9); // ≈1000 nits over the 203-nit reference
             let mut pc = [0f32; 16];
             pc[..12].copy_from_slice(bytemuck_rows(&rows));
-            pc[12] = 0.0; // SDR passthrough — PyroWave has no PQ path
-            pc[13] = 0.0;
+            pc[12] = mode;
+            pc[13] = peak;
             let bytes = std::slice::from_raw_parts(pc.as_ptr().cast::<u8>(), 64);
             self.device.cmd_push_constants(
                 self.cmd_buf,