Beacon 0.12.3-beta.4

This beta tightens Beacon’s first-run experience and performance on Macs with existing agent history.

• Older inactive sessions are set aside as quiet history on first launch. If you resume one later, it returns to Beacon automatically.
• Setup stays in front, buttons respond on the first click, and the walkthrough visibly advances as soon as Beacon finds a real session.
• Large Claude Desktop histories refresh with much less CPU work.