Effect-TS (v4) Patterns from effect-solutions and the Effect source. This covers the latest v4 APIs. Source-First Rule When working in any repo that uses Effect ( or in package/dependency files), reference the official Effect source before writing, reviewing, or refactoring Effect code. Do not rely on stale memory, blog posts, or high-level docs alone. - If the tool is available, use it for , , and instead of hand-rolled shell commands. - First check for a repo-local shallow source mirror at . - If it is missing, create it before doing Effect work: - Keep the mirror out of product commits. If…