tools: update clang/gcc support tables

[mathstuf]

GCC 14 will contain P1689 support. Clang 18 supports import std via libc++.

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Of course, even MSVC's C++20 module support should probably be "Partial" given that there are likely many bugs yet to be discovered.

[kelteseth]

Thank you 😊

[kelteseth]

@mathstuf Do you think we should add a tier level of support to modules? When looking at the comments of this PR, we can see that even using a none modules project as a dependency can make problems in a modules project. My proposal:

1. LibraryX can be used in a modules project
2. LibraryX itself is a modules project
3. All of LibraryX dependencies are modules
4. LibraryX uses C++23 import std;
5. All of LibraryX dependencies are using C++23 import std;

[mathstuf]

Tracking module-related issues might be useful? Something that works with compiler X and fails with Y might be worth tracking (with a link to an example project/standardese). There are definitely issues around mixing headers and modules today, but I believe there is work underway to address them.