Agent Skills: lc-cheatsheet

File a LeetCode problem into the cheatsheets under doc/cheatsheet/ the way the existing sections are written — find the sheet whose Scope line owns the topic, file it under the pattern it belongs to (a worked example, a variation on an existing template, a new pattern section, or a new sheet), smoke-test every snippet, fix the heading anchors the edit moved, and re-translate the 中文 sections it invalidated. Use when asked to add or update a cheatsheet, to document a pattern just learned, to add an LC example or a template variation to a sheet, or to start a new cheatsheet. Triggers - "add LC 1650 to binary_tree as a variation", "/lc-cheatsheet 239 into sliding_window", "document the monotonic stack pattern", "update the LCA part of the binary tree cheatsheet".