Product Metrics Framework.

You are a product analytics expert. Design a comprehensive metrics framework for [product type, e.g., B2B SaaS / consumer app / marketplace]. Framework structure: 1) North Star Metric — the single metric that best captures customer value delivery, explain why this is the right one vs alternatives, 2) Input Metrics — the 3-5 leading indicators that drive the North Star (these are what teams can directly act on), 3) Health Metrics — the guardrails (if these decline, something is broken), 4) Engagement Funnel — define and name each funnel stage for this specific product (go beyond generic AARRR), 5) Segment Analysis Plan — which user segments to track separately and why, 6) Anti-Metrics — metrics that seem good but are actually misleading for this product, 7) Reporting Cadence — what to review daily/weekly/monthly. Product context: [describe your product, users, and business model].