Add three new feature modules (reactions, bookmarks, polls) with corresponding database tables, indexes, and router registrations. Introduce `SESSION_MAX_AGE_REMEMBER` config for extended session duration, add `get_unread_messages` template global, and include operational defaults for rate limiting and session settings in `site_settings`.
Extract comment item building into `_build_comment_items` helper in database.py, import `get_recent_comments_by_post_uids` in feed router to attach up to 3 recent comments per post, add `post-card-comments` CSS class and `.comment-reply-form` margin rule, refactor `CommentManager` to use event delegation and toggle reply forms via a hidden template, move comment rendering into a reusable `_comment.html` macro, and include recent comments in `_post_card.html` with inline reply capability.
Introduce a new `/leaderboard` endpoint ranking top 50 members by total stars, wire it into the app router and documentation. Implement `_backfill_gamification()` in `database.py` to compute XP/levels for existing accounts from prior posts, comments, votes, and follows. Extract `is_owner()`, `create_content_item()`, and `detail_context()` into `content.py` to centralize content creation, reward awarding, mention notifications, and attachment linking. Update comment creation/deletion in `comments.py` to use `award_rewards()` with `XP_COMMENT` and the new `is_owner()` helper. Add shared template partials documentation for vote bars, star buttons, post headers, and topic selectors to `AGENTS.md`.
