Rework go to line infrastructure (#23654)

Closes https://github.com/zed-industries/zed/issues/12024


https://github.com/user-attachments/assets/60ea3dbd-b594-4bf5-a44d-4bff925b815f

* Fixes incorrect line selection for certain corner cases

Before:

<img width="1728" alt="image"
src="https://github.com/user-attachments/assets/35aaee6c-c120-4bf1-9355-448a29d1b9b5"
/>

After:

<img width="1728" alt="image"
src="https://github.com/user-attachments/assets/abd97339-4594-4e8e-8605-50d74581ae86"
/>


* Reworks https://github.com/zed-industries/zed/pull/16420 to display
selection length with less performance overhead.
Improves the performance more, doing a single selections loop instead of
two.

* Fixes incorrect caret position display when text contains UTF-8 chars
with size > 1
Also fixes tooltop values for this case

* Fixes go to line to treat UTF-8 chars with size > 1 properly when
navigating

* Adds a way to fill go to line text editor with its tooltip on `Tab`

Release Notes:

- Fixed incorrect UTF-8 characters handling in `GoToLine` and caret
position