feat: add live Gen5W telemetry dashboard

tests/NiroTelemetrySnapshotTest.php

@@ -0,0 +1,59 @@
+<?php
+declare(strict_types=1);
+
+if (PHP_SAPI !== 'cli') {
+    http_response_code(404);
+    exit;
+}
+
+require_once dirname(__DIR__) . '/NiroTelemetrySnapshot.php';
+
+function check(bool $condition, string $message): void
+{
+    if (!$condition) {
+        fwrite(STDERR, "FAIL: {$message}\n");
+        exit(1);
+    }
+}
+
+$now = time();
+$summary = NiroTelemetrySnapshot::summarize([
+    'received_at' => $now,
+    'availability' => 'online',
+    'state' => [
+        '_sample_epoch' => $now - 3,
+        'meta_system_dumpsys_ok' => 'true',
+        'meta_hscan_dumpsys_ok' => 'false',
+        'system_root_ign' => 'true',
+        'system_individualdrivemode_vehicle_speed' => '27',
+        'system_individualdrivemode_gear_status' => 'D(0x5)',
+        'system_root_mbatterysoc' => '93',
+        'hev_micom_hevstatus_mdisplaysoc' => '255',
+        'hev_micom_hevstatus_odometer' => '2596537',
+        'bcm_micom_bcmstatus_mdrvopenedstate' => '0',
+        'datc_micom_datcstatus_mambienttempc' => '25.0',
+        'mode_root_current_mode_real' => 'BLUETOOTH STREAMING (0x36)',
+    ],
+], ['stale_after' => 20]);
+
+check($summary['available'] === true, 'snapshot is available');
+check($summary['online'] === true, 'availability topic is respected');
+check($summary['stale'] === false, 'fresh sample is not stale');
+check($summary['metric_count'] === 11, 'metric count excludes sample epoch');
+check($summary['services'] === ['available' => 1, 'total' => 2], 'service health is counted');
+check($summary['metrics']['speed']['value'] === '27', 'speed mapping');
+check($summary['metrics']['gear']['value'] === 'D(0x5)', 'gear mapping');
+check($summary['metrics']['outside_temperature']['value'] === '25.0', 'climate mapping');
+check($summary['metrics']['driver_door']['supported'] === true, 'zero is supported');
+check($summary['metrics']['distance_to_empty']['supported'] === false, 'missing value is unsupported');
+check(!array_key_exists('state', $summary), 'raw snapshot is not exposed');
+
+$stale = NiroTelemetrySnapshot::summarize([
+    'received_at' => $now - 90,
+    'availability' => 'offline',
+    'state' => ['_sample_epoch' => $now - 90],
+], ['stale_after' => 20]);
+check($stale['online'] === false, 'offline state is exposed');
+check($stale['stale'] === true, 'old sample is stale');
+
+echo "PASS\n";