libcapsule: init at 0.20240806.0; libglcapsule: init; libGL: point to libglcapsule and make supporting changes

[Pandapip1]

Description of changes

Fixes #9415

Fixes #31189

This will allow for applications that depend on libGL to be run on non-NixOS platforms. This will particularly be useful in the context of nix bundlers, such as https://github.com/ralismark/nix-appimage.

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandboxing enabled in nix.conf? (See Nix manual)
  • sandbox = relaxed
  • sandbox = true
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 24.11 Release Notes (or backporting 23.11 and 24.05 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md.

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[NickCao]

I'm a bit confused about the purpose of libglcapsule, since we already have libglvnd, which is more or less fixing the same problem.

Edited: https://people.collabora.com/~vivek/libcapsule.pdf is very informative! "Call an isolated set of libraries a capsule" do sound like a good solution.

[liarokapisv]

Just commenting to check on the progress of this PR

[Pandapip1]

Just commenting to check on the progress of this PR

Progress: ??? / ???, and this isn't my top priority right now (college course load is currently higher than average). libcapsule and mkCapsule build, but I don't know if they really work.