test: Add edge case tests for ClearActiveAlerts and sanitizeAlertKey

- TestClearActiveAlertsEmptyMaps: tests early return when both maps empty
- sanitizeAlertKey: test for input with only slashes/backslashes -> root

Coverage improvement:
- sanitizeAlertKey: 96.4% → 100%
- alerts package: 52.8%

internal/alerts/alerts_test.go

@@ -4121,3 +4121,24 @@ func TestUnacknowledgeAlertSuccess(t *testing.T) {
 		t.Error("expected ackState entry to be deleted")
 	}
 }
+
+func TestClearActiveAlertsEmptyMaps(t *testing.T) {
+	t.Parallel()
+	m := NewManager()
+
+	// Ensure maps are empty initially
+	if len(m.activeAlerts) != 0 {
+		t.Fatalf("expected activeAlerts to be empty, got %d", len(m.activeAlerts))
+	}
+	if len(m.pendingAlerts) != 0 {
+		t.Fatalf("expected pendingAlerts to be empty, got %d", len(m.pendingAlerts))
+	}
+
+	// Call ClearActiveAlerts on empty manager - should return early without panic
+	m.ClearActiveAlerts()
+
+	// Verify maps are still empty (function returned early)
+	if len(m.activeAlerts) != 0 {
+		t.Errorf("expected activeAlerts to remain empty, got %d", len(m.activeAlerts))
+	}
+}

internal/alerts/utility_test.go

@@ -96,6 +96,11 @@ func TestSanitizeAlertKey(t *testing.T) {
 		},
 
 		// Edge cases
+		{
+			name:  "only slashes and backslashes becomes root",
+			input: "//\\\\",
+			want:  "root",
+		},
 		{
 			name:  "only special chars becomes disk",
 			input: "@#$%",