[Feature Request] SInput Protocol support #222

this is similar to #149, but this one is more geared towards SDL / Steam Input friendliness

basically; SInput protocol is a new WIP Protocol specifically designed for Steam Input and SDL3-based games while bypassing the realiance of emulating a existing Controller protocol (DS4, Switch Pro, XInput). That means: you can now have your Alpakka Controller be a bespoke Controller Type and be able to support Steam Input and SDL3-supported games natively without the need for an additional software. Even tho: Alpakka detects as "HID mouse, HID keyboard, and XInput or generic gamepad", Generic can become "HID Gamepad (via SInput)" and still provide the same feature sets.

You can see it in action right if you happen to have a GC Ultimate Controller or ProGCC and launch Steam Client. Even tho both of them are "GameCube", it's actually SInput under the hood.

note: if you got questions regarding "hey, how many Buttons it can take, how does it do LEDs, how can it communicate to Touch Input, etc", please refer to https://docs.handheldlegend.com/s/sinput/doc/sinput-hid-protocol-dev-SNSaEw36nc