Michael Schimmel
83324a1892
Add a new Markdown document detailing the AST node structure as it evolves through the compiler's different stages. This includes a diagram illustrating the data flow and relationships between the generic `Node<K, T>` structure and its specialized forms (`UntypedNode`, `BoundNode`, `TypedNode`, `AnalyzedNode`). The document explains the `kind` and `ty` payloads for each stage and their significance. Also removes a deleted file related to a previous optimization plan and adds new files for future optimization plans.