Get rid of transform in the annotation layer

[calixteman]

We have few bugs in Firefox because of that, the last I filed:
https://bugzilla.mozilla.org/show_bug.cgi?id=1770132

We could replace them with stuff like:

  top: calc(... * var(--zoom-factor));
  left: calc(... * var(--zoom-factor));
 ...

We already use this trick in order to set the font size in options:

pdf.js/src/display/annotation_layer.js

Line 1420 in 60e9065

const fontSizeStyle = `calc(${fontSize}px * var(--zoom-factor))`;

This way we could do the zoom stuff almost only thanks to css instead of relying on js.