ca2c85a8a4
Replaces the use of `BTreeMap` and `HashMap` for maps and records with `Vec<(Keyword, Value)>` and `Vec<(Keyword, StaticType)>`. This simplifies the data structure and allows for ordered iteration, which is important for serialization and comparison. Also updates the `unpack` function in `vm.rs` to handle records as well as lists when destructuring.