Report disk capacity in decimal GB so it matches Unraid and the drive label

The API mixes units per field — memory in bytes, disk size in KiB, fsSize and
fsUsed in kB — and one helper was guessing which from the magnitude of the
number, which also read any memory total under 100 GB as KB.

Plugin/unraid/include/common.php

@@ -448,8 +448,11 @@ function vv_disk_entry(array $d, string $key, string $role = 'data'): ?array {
         'name'      => $name,
         'device'    => $d['device'] ?? $key,
         'role'      => $role,
-        'size_gb'   => round($size_kb / 1048576, 1),
-        'used_gb'   => round($used_kb / 1048576, 1),
+        // disks.ini is KiB. This path was arithmetically right and still disagreed with the API
+        // path by 2.4% and with Unraid's own Main page by 7.4% — it produced GiB under a "GB"
+        // name. Decimal GB, so both sources of the same disk now land on the same number.
+        'size_gb'   => round($size_kb * 1024 / 1e9, 1),
+        'used_gb'   => round($used_kb * 1024 / 1e9, 1),
         'pct'       => (!$isParity && $size_kb > 0) ? round($used_kb / $size_kb * 100, 1) : null,
         'temp'      => is_numeric($tempRaw) ? (int)$tempRaw : null,
         'transport' => $d['transport'] ?? 'ata',
@@ -785,7 +788,7 @@ function vv_remote_hosts_stats(): array {
             $availBytes = (float)($mMem['available'] ?? 0);
             $memPct = $totalBytes > 0 ? (int)round(($totalBytes - $availBytes) / $totalBytes * 100) : 0;
         }
-        $memTotalGb = isset($mMem['total']) ? _vv_api_bytes_to_gb((float)$mMem['total']) : 0;
+        $memTotalGb = isset($mMem['total']) ? _vv_api_bytes_to_gib((float)$mMem['total']) : 0;
 
         $uptimeRaw = $os['uptime'] ?? '';
         if (is_numeric($uptimeRaw)) {