Cherry-picks for the godot-cpp 4.2 branch - 1st batch

[dsnopek]

The 1st batch of PR's marked with cherrypick:4.2

[AThousandShips]

See discussion on:

• Switch to 64-bit ints. #1357

I'd hold off cherry picking this, if at all (also for 4.1)

[dsnopek]

I'd hold off cherry picking this, if at all (also for 4.1)

We can hold off while figuring out the issue with SAFE_NUMERIC_TYPE_PUN_GUARANTEES(uint64_t), however, I'd really like to cherry-pick this eventually. Without this change, GDExtensions compiled with the 4.1 or 4.2 versions of godot-cpp will be subtly incompatible with Godot 4.3+ if they get a packed array or string with enough elements. And developers may choose to build their extension with the 4.1 or 4.2 version of godot-cpp to make it compatible with more versions of Godot.

[AThousandShips]

I'd suggest just removing it from this and not hold this batch back, will do some further looking into that bug but been having problems testing 32 bit builds, but will look back into it

[dsnopek]

Ok, I've removed the cherry-pick of PR #1357 for now

[AThousandShips]

LGTM (but made a few of these so a second opinion would be good too)