docs: add badges and dev quickstart

[AdekunleBamz]

This PR improves the repository landing page by adding useful status badges, correcting an inaccurate standards reference, and documenting basic local development commands.

Why

• README is the first touchpoint for contributors/users, and it was missing quick signals (CI status, license).
• The README claimed ERC-8021/ICodesRegistry support, but the repo does not contain an ICodesRegistry interface/implementation reference, which could confuse integrators.

Changes

• Add CI badge pointing to the repo’s GitHub Actions workflow.
• Add MIT license badge.
• Remove the inaccurate “ERC-8021 ICodesRegistry” claim from the intro.
• Add a small “Development” section with common Foundry commands.

Notes

• Local forge fmt --check showed formatting diffs in some existing test files under my Foundry version; I didn’t reformat unrelated files since this PR is docs-only.