better compatibility with search field and simpler CSS

Use more specific css rules for the emoji dimensions in the chat list status preview.

Use more round em value for chat list item height.
Add global html overflow and height for smoother chat navigation in
the desktop Safari.

Use offsetHeight instad of a computed style when setting the window height on resize.

Remove margin-bottom from the last message to avoid occasional layout shift in the desktop Safari

Use break-word to prevent chat message text overflow

Resize and scroll the textarea when inserting a new line on ctrl+enter

Remove fade transition on route change

Ensure proper border radius at the bottom of the chat, remove unused border-radius

Prevent the chat header "jumping" on the avatar load.

Reduces the size of the initial app bundle by about half.

generation for alerts, updated getTextColor to also have fallback to black/white
if resulting contrast isn't passable (only when inverting lightness!), updated
UI to use tabs.