Add Agentlas OS to Agent Frameworks

[Masonleenf]

Summary

• Add Agentlas OS to the Agent Frameworks section.
• Use the list's existing GitHub stars badge and one-line description format.
• Describe its local-first, model-agnostic Agent Operation Environment (AOE) scope.

Verification

• The repository link and stars badge target resolve.
• The entry is placed at the bottom of the appropriate section.
• git diff --check passes.

Disclosure: I am submitting this on behalf of Agentlas.