Add jar-cart to Build Tools

[Sudhanshu-Ambastha]

I am adding jar-cart to the Build Tools section, as requested in issue #1277.

jar-cart is a modern, zero-configuration dependency manager and runner for the Java ecosystem. It provides a lightweight, "npm-style" experience by utilizing Content Addressable Storage and native hard-linking to eliminate the latency and configuration overhead typically associated with traditional Java build systems.

• Unique approach: Enables "no-build" dependency management while maintaining interoperability with standard Maven/Gradle ecosystems.
• Developer experience: Focuses on speed, build-time performance, and simplified JDK provisioning.

Looking forward to your feedback!

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Summary by cubic

Add jar-cart to the Build Tools list in README.md to highlight a modern, zero‑config Java package manager and runner focused on speed and developer productivity. Addresses issue #1277.

^{Written for commit bbb8ba1. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 1 file

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