Improve media-poster component flexibility

[bienbiendev]

Related Problem:

Using web component :

It is not possible to pass specific attributes eg. fetchpriority="high" to the poster img.
As a workaround defining the img myself inside the media-poster ends with 2 img tag inside the media-poster.

Describe:

I'd like to be able to pass some other props to the img tag eg. loading="lazy" or fetchpriority="high".
Also it would be great to be able to define explicitly the img inside the media-poster.

This would fix some SEO issue :

• LCP repaint
• LCP request discovery