Co-authored-by: qcorradi <q.corradi22@imperial.ac.uk>
Co-authored-by: Zachary Snow <zach@zachjs.com>

- number literals are parsed rather than stored as strings
- fix array query functions used on non-trivial number literals
- more efficient expression simplification recursion
- expanded constant folding scenarios

- explicit enum casts in source are converted to size casts
- conversion for basic pattern array literals of unsized numbers
- unsized number array literals preserve signing
- more aggressive ternary simplification

- also adds $clog2 localparam substitution to Simplify