Add rightmodeler to Benchmark/Evaluator

[00-Aakash-00]

Summary

Adds one factual, open-source entry for rightmodeler in the Benchmark/Evaluator section.

Type of change

• Add new resource entry
• Update existing entry
• Remove outdated/invalid entry
• Formatting/typo only

Target section

• Benchmark/Evaluator

Quality checks (required)

• I searched README.md and confirmed this is not a duplicate.
• The submission is relevant to the AI agent ecosystem.
• The description is neutral and evidence-based (not promotional).
• I removed unverifiable claims (e.g., "best", "first") or provided clear evidence.
• License information is clear.
• The linked project has usable documentation.
• The OSS artifact has clear standalone value and this PR is not service promotion.

Proposed entry line

- [rightmodeler](https://github.com/elm-os/rightmodeler) - MIT-licensed TypeScript CLI that replays accepted agent traces through lower-cost candidate models and reports cost, agreement, sample size, and abstentions before a model change. ![GitHub Repo stars](https://img.shields.io/github/stars/elm-os/rightmodeler?style=social)

Evidence

• Repository and MIT license: https://github.com/elm-os/rightmodeler
• Documentation: https://www.rightmodeler.com/how-it-works

Affiliation: submitted on behalf of the rightmodeler team.