Replaced the grid layout (which made From row height depend on
cluster height, causing To/Cc to shoot up or down at the wrap
breakpoint) with a plain block stack:
- meta = position:relative block
- From row + details = natural block flow with padding-right
reserving space for the absolute cluster on the right
- cluster = position:absolute top-right, width changes per
container query (308px wide / 158px narrow / 180px overlay)
- padding-right tightens from 320px → 170px → 0 as the cluster
shrinks and finally goes overlay
- details margin-top dropped from -10px to 0 since there's no
grid row gap to compensate for
To/Cc now hugs From with no jumps when the cluster wraps or
overlays.
4913a1363b