Increase rounding for all embeds (#5421)

* tweak image styles

* fix reply image preview and covert to atoms

* increase rounding on media inset border

* decrease gap on desktop

* fix inset styles

* increase rounding on embeds to `md`

* Couple edge cases

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Co-authored-by: Eric Bailey <git@esb.lol>

src/components/MediaInsetBorder.tsx

@@ -24,7 +24,7 @@ export function MediaInsetBorder({
   return (
     <Fill
       style={[
-        a.rounded_sm,
+        a.rounded_md,
         a.border,
         opaque
           ? [t.atoms.border_contrast_low]