Port font to SDL3(_ttf)

[ankith26]

SDL3_ttf preview release: https://github.com/libsdl-org/SDL_ttf/releases/tag/preview-3.1.0

With this PR pygame.font compiles on SDL3(_ttf)

[Starbuck5]

Note to self: raise an issue about this.

It's a recent change, from libsdl-org/SDL_ttf#473

[damusss]

Edit: slightly incorrect, check further comments, point is still valid
A lot if not all TTF functions in sdl3 (I assume?) have 0 on success and -1 on error, like TTF_SizeText or TTF_Init, so checking if (TTF_X) {error} is actually wrong and should be if (TTF_X < 0) {error}. I know this PR is supposed to compile it, but without this an extra PR can't be avoided to fix this so you might aswell change it now.

[gresm]

Correction:
SDL3 uses more of the bool type and in many places it returns true (1) to indicate success and false (0) for failure. In SDL2 it is (0) for success (no error) and (-1) for failure, so if (SDL_Func() < 0) {err} and if (SDL_Func()) {err} works for SDL2 and if (!SDL_Func()) {err} for SDL3, so there's no version that would work for both SDL2 and SDL3, different code paths are needed.

[damusss]

Correction: SDL3 uses more of the bool type and in many places it returns true (1) to indicate success and false (0) for failure. In SDL2 it is (0) for success (no error) and (-1) for failure, so if (SDL_Func() < 0) {err} and if (SDL_Func()) {err} works for SDL2 and if (!SDL_Func()) {err} for SDL3, so there's no version that would work for both SDL2 and SDL3, different code paths are needed.

I said my 0 and -1 returns while looking at my IDE docstrings, but my IDE was actually looking at SDL2 functions, so no < 0 is incorrect and will never raise (that's why those bug errors disappeared) so yeah a not operator is needed like you said.

[gresm]

Some things that I've caught, definitely not checked exhaustively.