The Analyzer has been refactored to decorate `TypedNode`s with their
purity and recursion status. This involves creating a new `AnalyzedNode`
type and a `NodeMetrics` struct to hold this information. The `Analyzer`
now returns an `AnalyzedNode` instead of a separate `Analysis` struct.
This change lays the groundwork for future optimizations and analysis
passes.
Michael Schimmel
2fdeff1db4