Fix: never emit Infinity in health JSON (strict JSON for browsers)

aureon/core/aureon_operational_core.py

@@ -660,7 +660,7 @@ class StatePulse:
         """Check if state is stale (not updated recently)."""
         last = self._last_write.get('state', 0)
         if last == 0:
-            return True, float('inf')
+            return True, -1.0  # never written; -1.0 = unknown (never Infinity — strict JSON)
         age = time.time() - last
         return age > self._stale_threshold, age
 
@@ -669,7 +669,9 @@ class StatePulse:
         last = self._last_write.get('state', 0)
         return {
             'last_write': datetime.fromtimestamp(last).isoformat() if last > 0 else 'NEVER',
-            'age_seconds': now - last if last > 0 else float('inf'),
+            # None when never written: float('inf') would serialize as the literal
+            # `Infinity` token, which browsers cannot JSON.parse.
+            'age_seconds': now - last if last > 0 else None,
             'is_stale': (now - last > self._stale_threshold) if last > 0 else True,
             'write_count': self._write_count,
         }
@@ -911,7 +913,9 @@ class AureonOperationalCore:
 
         if state_freshness['is_stale']:
             health = 'degraded' if health == 'healthy' else health
-            issues.append(f"State stale: {state_freshness['age_seconds']:.0f}s old")
+            age = state_freshness.get('age_seconds')
+            stale_detail = 'never written' if age is None else f"{age:.0f}s old"
+            issues.append(f"State stale: {stale_detail}")
 
         return {
             'status': health,