Agent Skills: lisa-product-walkthrough

Methodology for evaluating the live product when planning work or evaluating a PRD. Reading a PRD or a mock without seeing the current product produces tickets that misjudge the change — this skill grounds the analysis in what actually exists today. Driving the product is owned by the `use-the-product` core (which detects the product type — DOM web, HTTP/API, canvas game, CLI, IaC — resolves the per-environment mutation policy from .lisa.config.json so production is never mutated by accident, and explores through the project's personas when defined); this skill adds the planning lens. Invoke from notion-to-tracker (Phase 2b live-product walkthrough), jira-create, and any PRD intake flow whose work touches existing user-facing surfaces.