feat(message): surface one-tap quick-reactions inline in the hover action rail

src/app/features/room/message/Message.tsx

@@ -116,6 +116,46 @@ export const MessageQuickReactions = as<'div', MessageQuickReactionsProps>(
   }
 );
 
+// Default reactions shown in the hover rail before a user has built up any
+// recent-emoji history, so the "быстрый рельс" always offers one-tap reactions.
+const RAIL_DEFAULT_REACTIONS: { unicode: string; shortcode: string }[] = [
+  { unicode: '👍', shortcode: 'thumbsup' },
+  { unicode: '❤️', shortcode: 'heart' },
+  { unicode: '😂', shortcode: 'joy' },
+];
+
+type RailQuickReactionsProps = {
+  onReaction: (key: string, shortcode?: string) => void;
+};
+// Inline quick-reactions surfaced directly in the hover action rail — react in
+// one tap without opening the emoji board. Mounts ONLY inside the
+// conditionally-rendered rail (one row at a time), so there is no per-row cost.
+function RailQuickReactions({ onReaction }: RailQuickReactionsProps) {
+  const mx = useMatrixClient();
+  const recent = useRecentEmoji(mx, 3);
+  const items =
+    recent.length > 0
+      ? recent.slice(0, 3).map((e) => ({ unicode: e.unicode, shortcode: e.shortcode }))
+      : RAIL_DEFAULT_REACTIONS;
+  return (
+    <>
+      {items.map((emoji) => (
+        <IconButton
+          key={emoji.unicode}
+          size="300"
+          variant="SurfaceVariant"
+          radii="300"
+          title={emoji.shortcode}
+          aria-label={emoji.shortcode}
+          onClick={() => onReaction(emoji.unicode, emoji.shortcode)}
+        >
+          <Text size="T400">{emoji.unicode}</Text>
+        </IconButton>
+      ))}
+    </>
+  );
+}
+
 export const MessageAllReactionItem = as<
   'button',
   {
@@ -914,6 +954,14 @@ const MessageInner = as<'div', MessageProps>(
           <div className={css.MessageOptionsBase}>
             <Menu className={css.MessageOptionsBar} variant="SurfaceVariant">
               <Box gap="100">
+                {canSendReaction && (
+                  <RailQuickReactions
+                    onReaction={(key, shortcode) => {
+                      const evtId = mEvent.getId();
+                      if (evtId) onReactionToggle(evtId, key, shortcode);
+                    }}
+                  />
+                )}
                 {canSendReaction && (
                   <PopOut
                     position="Bottom"