feat(host/windows): seal the host↔driver channels (frame + gamepad, proto v2)

Frame ring (pf-vdisplay) and both gamepad SHM channels move off named Global\
objects (openable by any sibling LocalService) to UNNAMED sections/events whose
handles the host DuplicateHandles into the driver's verified WUDFHost with least
access — frame delivery over the SYSTEM+admins-only IOCTL_SET_FRAME_CHANNEL,
pads over a 32-byte named bootstrap mailbox (pid + handle value only, DoS-bounded;
HID minidrivers have no control device). Driver-validated pad_index kills
cross-pad redirects; v1↔v2 mixes fail closed with diagnosis logs on both sides.
Sibling-LocalService denial proven empirically (design/idd-push-security.md,
design/gamepad-channel-sealing.md).

Driver-side raw ops now live behind pf-umdf-util (checked shm accessors, the
forbid(unsafe_code) ChannelClient state machine, WDF request tokens) — the pad
drivers' logic is 100% safe Rust; whole drivers workspace clippy-gated in CI.

driver install --gamepad now sweeps SWD\punktfunk phantom devnodes: a re-created
SwDevice REVIVES the old devnode with its previously-bound driver (never
re-ranks), so an upgrade otherwise leaves the old driver serving — or, across
the v1→v2 fence, a dead pad (found live on the RTX box).

On-glass validated on the RTX 4090 box: frame path 7007 frames p50 2.06 ms
cross-machine; DualSense + XUSB "sealed pad channel mapped"/proto=2 attach via
both the test harness and a real streaming session; phantom-sweep repro.

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

packaging/windows/drivers/pf-umdf-util/Cargo.toml

@@ -0,0 +1,17 @@
+# pf-umdf-util - the audited unsafe-primitive layer under the punktfunk UMDF gamepad drivers.
+# Everything a pad driver does with raw pointers or Win32/WDF FFI lives HERE, behind small safe
+# (or explicitly-contracted unsafe) APIs, so the driver crates' business logic is 100% safe Rust:
+#   section  - MappedView: bounds+alignment-checked shared-memory access (atomics for sync fields)
+#   channel  - ChannelClient: the sealed pad channel's driver-side state machine (a SAFE module)
+#   wdf      - Request/queue/device-property helpers over call_unsafe_wdf_function_binding
+[package]
+name = "pf-umdf-util"
+edition.workspace = true
+version.workspace = true
+license.workspace = true
+publish = false
+description = "punktfunk UMDF driver util: safe shared-memory + sealed-channel + WDF request primitives"
+
+[dependencies]
+wdk-sys.workspace = true
+pf-driver-proto.workspace = true