fix(game): add an event achievement filter

[wescopeland]

No description provided.

[greptile-apps]

Greptile Summary

Adds event visibility filtering to game-page achievement indicators.

• Hides future events from guests and ordinary users.
• Adds regression coverage for both audiences.

Confidence Score: 5/5

Safe to merge.

The filter follows existing event policy semantics and is regression-tested.

_{Reviews (1): Last reviewed commit: "fix(game): add an event achievement filt..." | Re-trigger Greptile}