Add Apple T2 SMC module

[ahowimocaj587-beep]

What changed

Adds an AppleT2Smc PawnIO module for the MMIO-based SMC interface found on Intel Macs with the Apple T2 chip (2018–2020).

The module exposes narrowly scoped IOCTL functions for:

• reading SMC keys and key metadata;
• looking up keys by index;
• writing fan-control keys only (F?Tg, F?Md, and FS! ).

Why

On T2 Macs, the legacy Apple SMC I/O-port interface does not return usable fan or temperature data under Windows. The controller is instead exposed through an MMIO window. A signed PawnIO module is needed so Windows applications can access that interface without bundling a general-purpose raw-memory driver.

The register layout and handshake follow the Linux T2 applesmc implementation from MCMrARM/mbp2018-etc.

Safety

The module probes the mapped status register before becoming available. Kernel-side write filtering prevents arbitrary SMC writes and permits only fan target/mode keys.

Validation

• Compiled successfully with Pawn compiler 4.1.7152 using the repository CI-equivalent flags: -C64 -;+ -(+ -p.
• Confirmed the target Mac exposes ACPI\\APP0001 with an MMIO resource at 0xFE0B0000.
• Hardware protocol validation is pending a build signed for PawnIO Official edition; the current official driver correctly refuses the locally unsigned module.

This PR is intentionally a draft until maintainers can review the MMIO and write-filtering behavior.