Support Pico on OpenXR

[mikeskydev]

Adds Android input mappings for Pico devices to OpenXR using their official plugin, mirrored to Icosa's mirror repo.
Need to test against other platforms.

[mikeage]

it looks like the Pico builds failed; are any changes needed to build.yml?

[mikeage]

If I'm not mistaken, the clash is not between Oculus and Pico, but rather Pico-from-git and Pico-from-zip

[mikeskydev]

Correct, but both a result of pico copying oculus' meta files, and then additionally using the meta files/code in both of their packages, a big no no 😂

[mikeage]

But didn't you fix that in the both the git mirror and in our build script? I don't think the problematic Common.cs.meta file is actually found anywhere, is it?

Actually, looking more carefully at the logs, isn't it because of this:

Library/PackageCache/com.unity.xr.openxr.picoxr@0c6e35dbf6/Platform/Editor/PicoGs.cs(37,55): error CS1061: 'PXR_PlatformSetting' does not contain a definition for 'useHighlight' and no accessible extension method 'useHighlight' accepting a first argument of type 'PXR_PlatformSetting' could be found (are you missing a using directive or an assembly reference?)
Library/PackageCache/com.unity.xr.openxr.picoxr@0c6e35dbf6/Platform/Editor/PicoGs.cs(40,46): error CS1061: 'PXR_PlatformSetting' does not contain a definition for 'useHighlight' and no accessible extension method 'useHighlight' accepting a first argument of type 'PXR_PlatformSetting' could be found (are you missing a using directive or an assembly reference?)