wayland: Add multi-seat support #5383

Job	Run time
Create test plan	4s
level1 / Haiku	1m 42s
level2 / Sony PlayStation Portable	3m 56s
level2 / LoongArch64	1m 58s
level2 / Ubuntu 22.04	3m 40s
level2 / Windows (MSVC, x86)	6m 19s
level2 / Windows (MSVC, x64)	6m 9s
level2 / Sony PlayStation Vita (GLES w/ PVR_PSP2)	3m 2s
level2 / GDK (MSVC, x64)	2m 47s
level2 / Sony PlayStation 2	5m 4s
level2 / Steam Linux Runtime (Sniper)	3m 15s
level2 / Windows (msys2, mingw64)	4m 56s
level2 / Android (Gradle)	2m 30s
level2 / iOS (CMake & xcode)	2m 28s
level2 / NetBSD	2m 53s
level2 / Windows (msys2, clang64)	4m 35s
level2 / Windows (MSVC, ARM64)	4m 34s
level2 / Ubuntu 22.04 (Intel oneAPI)	5m 21s
level2 / Ubuntu 22.04 (Intel Compiler)	5m 33s
level2 / FreeBSD	2m 49s
level2 / Sony PlayStation Vita (GLES w/ pib)	3m 2s
level2 / Android (CMake)	3m 40s
level2 / Android (CMake, lean)	2m 3s
level2 / MacOS (Framework) (arm64)	2m 5s
level2 / Windows (MSVC, clang-cl x86)	6m 26s
level2 / PowerPC64	2m 5s
level2 / RISC OS	1m 23s
level2 / Emscripten	8m 31s
level2 / MacOS (Framework) (x64)	5m 39s
level2 / MacOS (GNU prefix)	2m 53s
level2 / Android (Android.mk)	1m 13s
level2 / Windows (msys2, mingw32)	5m 45s
level2 / PowerPC	2m 4s
level2 / Nintendo 3DS	2m 0s
level2 / Windows (msys2, ucrt64)	5m 20s
level2 / Ubuntu 24.04 (ARM64)	5m 24s
level2 / Windows (MSVC, ARM)	4m 23s
level2 / Windows (MSVC, clang-cl x64)	5m 46s
level2 / tvOS (CMake & xcode)	1m 59s
	2h 25m 16s

Provide feedback