feat(archive): implement comment.archived and add archive page (#1074)

* feat(archive): implement comment.archived and add archive page

Add isCommentArchived() utility, /board/:boardIdentifier/archive route,
archive view with filtered feed, and UI integration (board buttons, edit
menu, catalog row, post). Archived indicator on catalog and posts.

* fix(archive): address review feedback from Bugbot and CodeRabbit

Add missing i18n keys (archived, thread_archived, view, loading_archive),
add /archive/settings route, replace hardcoded English in archive.tsx, and
fix mobile test state.

src/lib/utils/comment-moderation-utils.ts

@@ -0,0 +1,15 @@
+type MaybeArchivedComment = {
+  archived?: boolean;
+  commentModeration?: {
+    archived?: boolean;
+  };
+};
+
+export const isCommentArchived = (comment: unknown): boolean => {
+  if (!comment || typeof comment !== 'object') {
+    return false;
+  }
+
+  const archivedComment = comment as MaybeArchivedComment;
+  return Boolean(archivedComment.archived || archivedComment.commentModeration?.archived);
+};