Social Feed

# Social Feed PRD

## Overview
Build a social media feed application with post creation, commenting with threaded replies, likes, infinite scroll, and rich text formatting.

## Requirements
- Create posts with text content and optional image URL
- Post feed with infinite scroll loading
- Like and unlike toggle with live count display
- Comment on posts with threaded reply support
- User avatars and display names using mock data
- Relative timestamps (e.g., "2 min ago", "1 day ago")
- Post menu with edit and delete for own posts
- Rich text in posts: bold, italic, and auto-detected links
- Image preview displayed inline in posts
- Character limit of 280 characters with live counter
- Share and repost functionality
- Bookmark and save posts for later
- Filter feed by: all posts, following, and bookmarked
- Search across all posts by content
- New post notification banner when new content is available
- Persist all data to localStorage

## Tech Stack
- JavaScript or any frontend framework
- CSS for feed layout and animations
- No social media component libraries

## Scoring Criteria
- **Functional (40%)**: Post CRUD works, comments and likes work, infinite scroll loads
- **Quality (20%)**: Smooth scrolling, proper state management, clean UI
- **Fidelity (25%)**: All features present including threaded replies, rich text, bookmarks, and search
- **Speed (15%)**: Time bonus