[WIP] Update the README to better reflect the current status of the package

[Copilot]

Thanks for asking me to work on this. I will get started on it and keep this PR's description up to date as I form a plan and make progress.

Original description:

Please update the README to better reflect the current status of the package, and make sure it has a pedagogical example showcasing the package.

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[github-actions]

Bencher Report

Branch	copilot/fix-d4f9e703-cdaf-466d-8978-ae12e8b5e659
Testbed	pmcore-runner

Click to view all benchmark results

Benchmark	Latency	Benchmark Result seconds (s) (Result Δ%)	Upper Boundary seconds (s) (Limit %)
bimodal_ke_npag	📈 view plot 🚷 view threshold	14.87 s (+0.17%) Baseline: 14.84 s	22.92 s (64.87%)
bimodal_ke_npod	📈 view plot 🚷 view threshold	9.24 s (-1.17%) Baseline: 9.35 s	10.71 s (86.28%)
bimodal_ke_postprob	📈 view plot 🚷 view threshold	3.27 s (-0.58%) Baseline: 3.28 s	3.54 s (92.14%)

🐰 View full continuous benchmarking report in Bencher