gui_toolkit 0.101.0

Changed

• The library's packages are in src/ (src/ui, src/platform...): a program's collection points there (-collection:gt=<toolkit>/src), and the examples, tests, tools and docs apart from it. Every step is a command of tools/tk, on Windows and Linux: build (an example; build.bat and ./build.sh are its shortcuts), ci (what tools/linux_ci.sh did), desktop_tests (what tools/linux_desktop.sh did, its fake xdg-open an Odin program), build_text on Linux too. The scripts are gone. flake.nix: the development shell on Linux (the pinned Odin with wgpu-native, Rust, the virtual desktops' servers).