Fix tor configuration append / graph visualization

web/api/stats.php

@@ -1,7 +1,16 @@
 <?php
-require __DIR__ . '/../lib/app.php'; auth_require();
+require __DIR__ . '/../lib/app.php';
+auth_require();
+
 header('Content-Type: application/json');
-$path = "/var/lib/torpanel/stats.json";
-if (!file_exists($path)) { echo json_encode(["data"=>[]]); exit; }
+header('Cache-Control: no-store, no-cache, must-revalidate, max-age=0');
+header('Pragma: no-cache');
+
+$path = '/var/lib/torpanel/stats.json';
+if (!is_readable($path)) {
+  echo json_encode(['data' => []]);
+  exit;
+}
+
 $raw = file_get_contents($path);
-echo $raw ?: json_encode(["data"=>[]]);
+echo $raw !== false && $raw !== '' ? $raw : json_encode(['data' => []]);