Agent Skills: lc-site-data

Add a topic to the Study Roadmap (data/roadmap.json) or a question to the Complexity Quiz (data/complexity_quiz.json), satisfying the build-time validators in one pass — a row strictly below every prereq, no cycle and no edge the graph already implies, sheet slugs and LC numbers that exist, no duplicate quiz id, accept always an array, and every answer parseable by site/complexity.js's single-letter identifiers. Use when asked to add a roadmap topic, wire a topic's prerequisites, add a complexity question or drill, or fix a build that a roadmap or quiz entry failed. Triggers - "add monotonic stack to the roadmap", "/lc-site-data quiz for LC 239", "add a complexity question", "the roadmap build is failing".