Expand Aliases

[rcosta358]

Closes #160. Adds a new AliasExpansion pass that adds the alias body as an origin of an alias invocation, substituting its parameters with the provided arguments. Works by extracting the aliases from the context and passing them to the simplification logic. We reuse the ValDerivationNode to represent alias expansions, which is enough for this purpose and avoids requiring changes to the VS Code extension.

Example

When we invoke the alias Byte(int b) { b >= -128 && b <= 127 }") with Byte(#v_8), we get:

{
  "value": "Byte(#v_8)",
  "origin": {
    "value": "#v_8 >= -128 && #v_8 <= 127"
  }
}