feat(windows-drivers): STEP 7 — HDR/FP16 (validated on-glass: Mac connects WITH HDR)

The pf-vdisplay driver now advertises HDR/FP16 and the full glass-to-glass HDR path works
end-to-end — validated LIVE: the Mac client connected to the .173 host WITH HDR (display_hdr=true,
FP16 ring -> NVENC P010). The STEP-3 assumption that FP16 needs a higher UmdfExtensions was WRONG:
IddCx0102 + CAN_PROCESS_FP16 + the *2 DDIs works (the oracle proved it; confirmed on-glass
IddCxAdapterInitAsync -> 0x0 WITH the FP16 cap set). Driver-only change — the host FP16-ring ->
NVENC-P010 path and the HDR EDID were already in place.

- adapter.rs: caps.Flags = IDDCX_ADAPTER_FLAGS_CAN_PROCESS_FP16.
- entry.rs: register the 6 *2/HDR callbacks (ParseMonitorDescription2, MonitorQueryTargetModes2,
  AdapterCommitModes2, AdapterQueryTargetInfo, MonitorSetDefaultHdrMetaData, MonitorSetGammaRamp)
  ALONGSIDE the v1 set (matching the oracle — CAN_PROCESS_FP16 OBLIGATES the *2 DDIs or the
  framework rejects the adapter at init; STEP 3 rejected FP16 only because they weren't registered).
- callbacks.rs: parse_monitor_description2 + monitor_query_modes2 now fill IDDCX_MONITOR_MODE2 /
  IDDCX_TARGET_MODE2 with BitsPerComponent (8|10 bpc RGB); query_target_info already reports
  IDDCX_TARGET_CAPS_HIGH_COLOR_SPACE; set_default_hdr_metadata + set_gamma_ramp accept (the gamma
  one is mandatory under FP16).
- monitor.rs: wire_bits() (Rgb 8|10, no YCbCr) + target_mode2().
- EDID + INF UNCHANGED (the EDID already carries the CTA-861.3 BT.2020 + ST.2084/PQ block; the INF
  stays UmdfExtensions=IddCx0102).

Built via the ultracode flow (STEP-7 map workflow -> agent-implement -> box build [driver green] ->
deploy -> on-glass HDR). OPERATIONAL NOTE: do NOT Disable/Enable the IddCx devnode to reload it —
that leaves the adapter STOPPED in the persisted WUDFHost process (ADAPTER OnceLock survives), so
monitor-create then fails with 0xc00002b6 (INDIRECT_DISPLAY_DEVICE_STOPPED). Kill the pf_vdisplay
WUDFHost process (or reboot) for a clean adapter re-init.

This completes the pf-vdisplay rewrite STEP 0-7, all on-glass validated (loads, adapter inits,
monitor appears, swap-chain drain, IDD-push frames at ~235fps, and HDR). Remaining: STEP 8 (unsafe-
reduction + delete the old vdisplay-driver tree + the vendored SudoVDA driver + unbundle from the
installer = the SudoVDA drop).

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

packaging/windows/drivers/pf-vdisplay/src/monitor.rs

@@ -142,6 +142,35 @@ pub fn target_mode(width: u32, height: u32, refresh_rate: u32) -> iddcx::IDDCX_T
     tm
 }
 
+/// Wire bit-depth advertised per mode in the `*2` (HDR) mode DDIs. STEP 7: advertise BOTH 8 and 10 bpc
+/// RGB (so the OS offers HDR10 modes), no YCbCr. The wdk-sys bindgen enum is `ModuleConsts`, so each
+/// `IDDCX_BITS_PER_COMPONENT_*` is a plain-int const and the `IDDCX_WIRE_BITS_PER_COMPONENT` fields are
+/// plain ints — OR the constants directly (NO newtype `.0` like the oracle's wdf-umdf-sys binding). Field
+/// names (Rgb/YCbCr444/YCbCr422/YCbCr420, IDDCX_BITS_PER_COMPONENT_8/_10/_NONE) are the verbatim C header
+/// names, identical across both bindings.
+pub fn wire_bits() -> iddcx::IDDCX_WIRE_BITS_PER_COMPONENT {
+    let rgb = iddcx::IDDCX_BITS_PER_COMPONENT::IDDCX_BITS_PER_COMPONENT_8
+        | iddcx::IDDCX_BITS_PER_COMPONENT::IDDCX_BITS_PER_COMPONENT_10;
+    let mut w: iddcx::IDDCX_WIRE_BITS_PER_COMPONENT = unsafe { core::mem::zeroed() };
+    w.Rgb = rgb;
+    w.YCbCr444 = iddcx::IDDCX_BITS_PER_COMPONENT::IDDCX_BITS_PER_COMPONENT_NONE;
+    w.YCbCr422 = iddcx::IDDCX_BITS_PER_COMPONENT::IDDCX_BITS_PER_COMPONENT_NONE;
+    w.YCbCr420 = iddcx::IDDCX_BITS_PER_COMPONENT::IDDCX_BITS_PER_COMPONENT_NONE;
+    w
+}
+
+/// `IDDCX_TARGET_MODE2` for a scan-out mode (HDR `*2` path): builds the v1 [`target_mode`] and copies its
+/// `TargetVideoSignalInfo`, then stamps the `*2` Size + per-mode wire bit-depth ([`wire_bits`]). Rest
+/// zeroed.
+pub fn target_mode2(width: u32, height: u32, refresh_rate: u32) -> iddcx::IDDCX_TARGET_MODE2 {
+    let m1 = target_mode(width, height, refresh_rate);
+    let mut tm: iddcx::IDDCX_TARGET_MODE2 = unsafe { core::mem::zeroed() };
+    tm.Size = core::mem::size_of::<iddcx::IDDCX_TARGET_MODE2>() as u32;
+    tm.TargetVideoSignalInfo = m1.TargetVideoSignalInfo;
+    tm.BitsPerComponent = wire_bits();
+    tm
+}
+
 /// A monitor's advertised modes (the looked-up entry returns a clone for lock-free mode-DDI fill).
 pub fn modes_for_id(id: u32) -> Option<Vec<Mode>> {
     MONITOR_MODES