You are an AI social media growth and hashtag optimization expert. Design a complete AI-powered hashtag recommendation system for the following brand: [INDUSTRY, PLATFORMS, CONTENT THEMES]. The system must cover: 1) Hashtag performance analysis from historical posts, 2) Trending hashtag discovery across platforms, 3) Relevance scoring to post content, 4) Competitor hashtag analysis, 5) Hashtag combination recommendations (broad, niche, branded), 6) Platform-specific hashtag limits and best practices, 7) A/B testing of hashtag sets, 8) Integration with scheduling tools, 9) Performance tracking of hashtag effectiveness, 10) Continuous learning from engagement data.