reaction window should not have fixed width.

[vibbe]

Describe the bug

the reaction window should not have a fixed width instead use % of the window.
if you added some more reactions then the default window should be fine, but more reactions are added it should perhaps have a [more] expandable window or use % of window or both.

see image for details

Steps to reproduce

See image.

Possible solution would be % and not fixed size since user both use browsers and phone.
another possible solution would be to have [more] link to expansible function.

The version of Memos you're using

0.25.1

Screenshots or additional context