Every module unit now includes the standard headers it uses. Declarations
reaching a unit only through an imported module's global module fragment
are reachable but not visible, so ADL misses the free operators older
libstdc++ declares beside a type - reproduced on ubuntu 24.04 (libstdc++
13), where gl/vao.cpp could not compare vector iterators.
Also drops a stale editor/editorSettings.hpp from the MSVC source list,
which broke the Windows configure step, silences the deliberate
include-in-purview warning in the glm wrapper, and removes GCC support:
clang or MSVC only.
Linux CI switches to clang 22; fixes what that exposed - export on
out-of-line member definitions, missing std includes, missing glm
imports. GCC 16 still builds.
In TSegment there were two different formulas for a derivative. Most places called GetFirstDerivative() that used the direct formula from the curve points. However RaPositionGet() had its own calculation based on pre-computed cubic polynomial coefficients. This latter method is faster and simpler, so change GetFirstDerivative() to use it and change RaPositionGet() to just call GetFirstDerivative().
TSegment::GetTFromS() is a significant hotspot in the non-rendering part of the state_manager update (about 13%). This change introduces a FastGetTFromS() version that interpolates from precomputed values instead of doing the whole calculation on every call. Computing position from track distance is now done in constant time. This reduces the contribution to about 0.3%.
