Fix center viewport not working horizontally

[kitbdev]

• fixes Searching in script editor does not scroll horizontally to result #93762

The wrap condition was inverted, so it never moved horizontally.
It's part of center_viewport_to_caret but it adjusts the caret horizontally instead of centering it intentionally to match other editors, so searching only moves the horizontal scrollbar if needed.
I changed it a bit so that it checks both ends of selected text if it is on one line, so searching for text makes sure it is on screen.
Also added a guard to adjust_viewport_to_caret to match.

[kitbdev]

Rebased and fixed conflict.
Moved it into a helper function, because adjust to caret does the same thing.
Split Vector2i caret_pos into 2 ints, since it is never used as a Vector2i and it is more descriptive this way.
Also removed 3 unrelated function definitions. (see #92514 and #92865)

Now also makes adjusting to caret on a single line right-to-left selection show as much of it as it can (ex undoing something).

There is code to scroll to the IME, but it's not working for me, see #101601
I treated the code as if it works for now, the logic should basically be the same.

[KoBeWi]

Needs rebase.

[kitbdev]

Rebased
Made sure it works with IME after the fix for it.

• related [TextEdit] Fix viewport_to_caret using start of IME text instead of IME caret/selection. #101629

Cleaned up the logic a little.

[Repiteo]

Thanks!