fix(feed): more vertical gap between header and post content

marginTop 8 → 14 on the content Pressable. Gives the body text a
clear visual separation from the avatar/name header instead of
sitting flush under it.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

client-app/components/feed/PostCard.tsx

@@ -255,7 +255,7 @@ function PostCardInner({ post, likedByMe, onStatsChanged, onDeleted, compact }:
         onPress={onOpenDetail}
         onLongPress={onLongPress}
         style={({ pressed }) => ({
-          marginTop: 8,
+          marginTop: 14,
           overflow: 'hidden',
           opacity: pressed ? 0.85 : 1,
         })}