contrib/surface: add Surface Pro/Laptop x86-64 bootc example (systemd-boot, linux-surface, TPM2)

[corning-croak-cable]

Surface Pro / Surface Laptop - x86-64 UEFI (contrib example)

Adds example Containerfile and supporting config for building a bootc-compatible
OCI image for Microsoft Surface Pro and Surface Laptop (x86-64) devices.

Files (contrib/surface/x86/)

contrib/surface/x86/
  Containerfile.fedora                          # Fedora-based OCI image (linux-surface kernel)
  usr/lib/bootc/install/50-surface-x86.toml    # install config: systemd-boot, DPS, kargs
  usr/lib/bootc/kargs.d/50-surface-x86.toml    # persistent kargs (PSR, deep sleep, lid fix)
  usr/lib/modprobe.d/surface-x86.conf           # usbhid poll rate, pcspkr blacklist
  usr/lib/udev/rules.d/99-surface-typecover.rules  # Type Cover wakeup-from-suspend
  usr/lib/systemd/sleep.conf.d/surface-x86.conf    # prefer S3 deep sleep
  usr/lib/systemd/system-preset/15-surface-x86.preset  # enable iptsd, thermald
  README.md

Install config design (verified from config.rs)

Field	Value	Reason
match-architectures	["x86_64"]	Only applied on x86-64 hosts (verified: test_arch() in config.rs)
bootloader	"systemd"	Surface UEFI is standard EFI; systemd-boot works natively
discoverable-partitions	true	Enabled when systemd-boot is selected (BLI always implemented)
block	["direct", "tpm2-luks"]	Both allowed; user selects via --block-setup at install
kargs	PSR off, deep sleep, lid fix	Surface-specific ACPI/i915 quirks

Build and install

podman build --platform linux/amd64 -f contrib/surface/x86/Containerfile.fedora -t surface-x86 .
podman run --rm --privileged --pid=host -v /dev:/dev surface-x86 bootc install to-disk /dev/nvme0n1