Add Tree Ring Memory

[TerminallyLazy]

Summary

Adds Tree Ring Memory to the AI Agent Memory & Context table.

Type of Change

• New tool/resource
• Update existing entry
• Fix broken link
• Improve documentation
• Other (please describe)

Checklist

• I have read the CONTRIBUTING guidelines
• Tool/resource follows the awesome list format
• Links are working and tested
• Entry includes the fields used by this section: Tool name, Type, Why It's Awesome
• No promotional/marketing language (focus on utility)
• Alphabetical order maintained (if applicable)

Additional Context

Tree Ring Memory is a framework-agnostic Rust CLI memory layer for coding agents, with local recall, forgetting, audit, and TUI workflows.