privacy: enforce freshness for queued geofence coordinates #21

Scope

Separate geofence event retention from coordinate freshness.

Required behavior

• Carry event timestamp with transition coordinates
• Enforce a short documented coordinate-freshness limit
• Fetch a fresh location or omit location template values when queued coordinates are stale
• Fresh event coordinates continue to avoid redundant location requests

Evidence

• GeofenceTracker.kt:280-289
• LocationDependency.kt:28-35
• AutomationEngine.kt:470-516

Tests

Stale event coordinates invoke fresh provider or omit values; fresh coordinates bypass provider.

Audit: 0a39f7e.