feat: Introduce custom emojis, pinned comments, and thread locking features, while filtering deleted comments from API responses and refining comment root finding logic.

public/s/js/comments.js

@@ -133,7 +133,7 @@ class CommentSystem {
             } else {
                 // It's a reply - find root and attach there
                 const root = findRoot(c);
-                if (root) {
+                if (root && root !== c) {
                     // If replying to a non-root, capture the username for @mention
                     const directParent = map.get(c.parent_id);
                     if (directParent && directParent.id !== root.id) {