refactor(host/W6.2): extract the Windows display-topology cluster into the pf-win-display leaf crate

windows/{win_display,monitor_devnode,display_events}.rs move into
crates/pf-win-display: the CCD/GDI path-activation + mode-set + HDR
advanced-colour + source-rect helpers, the PnP monitor-devnode enable/disable
lever, and the WM_DISPLAYCHANGE / device-arrival watch. The coming pf-capture
crate's IDD-push capturer consumes all three; the host's pf-vdisplay backend
consumes win_display + monitor_devnode. A leaf lets both depend on them as a
PEER instead of the capturer reaching back into the orchestrator (plan §W6).

win_display's one external tie (crate::vdisplay::Mode) becomes the underlying
punktfunk_core::Mode; the cluster is otherwise self-contained (pf-paths for the
state file, serde_json for it, windows). pub(crate) items bump to pub at the
boundary; win_display carries a module-level allow(missing_safety_doc) to keep
the pre-carve behavior (the FFI helpers were pub(crate) unsafe fn with prose
safety docs — the lint only fires once they're pub, and this is an internal
publish=false leaf). The host imports the three modules at its crate root, so
every crate::{win_display,monitor_devnode,display_events}::* path is unchanged.

Verified: Linux clippy -D warnings (leaf empty + host
nvenc,vulkan-encode,pyrowave --all-targets); Windows clippy -D warnings
(pf-win-display --all-targets + host nvenc,amf-qsv --all-targets) Finished exit 0.

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

Cargo.lock

@@ -2860,6 +2860,18 @@ dependencies = [
  "windows-sys 0.61.2",
 ]
 
+[[package]]
+name = "pf-win-display"
+version = "0.12.0"
+dependencies = [
+ "anyhow",
+ "pf-paths",
+ "punktfunk-core",
+ "serde_json",
+ "tracing",
+ "windows 0.62.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "pf-zerocopy"
 version = "0.12.0"
@@ -3177,6 +3189,7 @@ dependencies = [
  "pf-gpu",
  "pf-host-config",
  "pf-paths",
+ "pf-win-display",
  "pf-zerocopy",
  "pipewire",
  "punktfunk-core",