[Typing] Use SVG or CSS animation for typing indicator instead of GIF for reduced motion

[compulim]

Is your feature request related to a problem?

To enable reduced motion, we should use SVG/CSS which its animation is more controllable than GIF.

Describe the suggestion or request in detail

No response

Describe alternatives you have considered

No response

Additional context

No response

[OEvgeny]

We can use SVG animations as SMIL is back, not deprectated anymore: https://developer.mozilla.org/en-US/docs/Web/SVG/SVG_animation_with_SMIL

Or we can use SVG with CSS animations which allows us to handle reduced motion media: https://developer.mozilla.org/en-US/docs/Web/SVG/Element/animate#accessibility_concerns

[compulim]

I will choose SVG + CSS for reduced motion, so it's easier for us to write VRT too.