Describes every RustQ AST node: its category, fields, and the Rust constant and module
names the generated native decoders use for it. RustQ's self-hosted code generation
reads it to build generated_ast.rs.
Summary
Functions
@spec nodes() :: [RustQ.Rust.AST.Schema.Node.t()]
@spec nodes(atom()) :: [RustQ.Rust.AST.Schema.Node.t()]