feat: Add ix compile CLI and CI benchmarks

[samuelburnham]

This PR adds the following:

• ix compile CLI command
• Library suite in Benchmarks/Compile for use in benchmarking Ix compilation time
• CI benchmark for each library, run on every push to main
• formal-conjectures benchmark, which doesn't currently work due to the repo's Lean version being out of date (v4.22.0)

The compiler benchmark workflow runs on every push to main, and manually with workflow_dispatch once merged. A test run can be viewed at https://github.com/argumentcomputer/ix/actions/runs/21924965628.

Future work:

• Host a web page with ix compiler performance over time
• Profiling and instrumentation to further improve performance and debugging