Jittering positioning of the `TextAnnotatorPopup` on scroll

[oleksandr-danylchenko]

Issue

When the text selection stops higher up in the content and then you start scrolling up/down, the popup starts to jump over the selection range:

sporadic_movement.mov

Personally, I find that kinda distracting, especially on smaller screen sizes:

Screen.Recording.2024-07-12.at.18.29.47.mov

Also, with autoPlacement the popup is constantly displayed over the annotated content

Suggested Changes

We can use a more temperate positioning like top + inline() middleware. Additionally, we can limit the crossAxis scrolling and let the user scroll from the popup. Which feels a bit more pleasant and intuitive (IMHO).

Existing solutions

The visual example I like is the Slab.com:

[oleksandr-danylchenko]

Moreover, after I added the keyboard selection support in #118, I found that I could accidentally make the page freeze after pressing Ctrl+A. I narrowed it down to the popup positioning unable to find a suitable place and running into an endless loop.