Fix version fallback: use 0.0.0 with error flag when version.php is missing or invalid

- handleUpdate(): set versionError flag and return 0.0.0 if version.php missing/invalid
- Dashboard stats: use 0.0.0 fallback instead of '-' when version cannot be determined
- Makes version.php truly required as intended

public/admin.php

@@ -215,7 +215,14 @@ function handleDashboard(AdminAuth $auth, array $config): void
     $configJson = $config['config_json'];
 
     $versionFile = __DIR__ . '/../version.php';
-    $versionInfo = file_exists($versionFile) ? include $versionFile : [];
+    $versionInfo = [];
+    if (file_exists($versionFile)) {
+        $verData = include $versionFile;
+        $versionInfo = is_array($verData) ? $verData : [];
+    }
+    if (empty($versionInfo['version'])) {
+        $versionInfo['version'] = '0.0.0';
+    }
 
     $stats = [
         'pages' => countFiles($contentDir, ['md', 'php', 'html']),
@@ -224,7 +231,7 @@ function handleDashboard(AdminAuth $auth, array $config): void
         'config_exists' => file_exists($configJson),
         'content_size' => formatSize(dirSize($contentDir)),
         'php_version' => PHP_VERSION,
-        'cms_version' => $versionInfo['version'] ?? '-',
+        'cms_version' => $versionInfo['version'],
         'os' => PHP_OS_FAMILY . ' (' . php_uname('r') . ')',
     ];
 
@@ -1834,10 +1841,19 @@ function handleUpdate(AdminAuth $auth, array $config): void
 
     // Load CMS version
     $versionFile = $config['codepress_root'] . '/version.php';
-    $cmsVersion = '1.7.1';
-    if (file_exists($versionFile)) {
+    $cmsVersion = '0.0.0';
+    $versionError = false;
+    if (!file_exists($versionFile)) {
+        $versionError = true;
+        $cmsVersion = '0.0.0';
+    } else {
         $verData = require $versionFile;
-        $cmsVersion = is_array($verData) ? ($verData['version'] ?? '1.7.1') : '1.7.1';
+        if (!is_array($verData) || empty($verData['version'])) {
+            $versionError = true;
+            $cmsVersion = '0.0.0';
+        } else {
+            $cmsVersion = $verData['version'];
+        }
     }
 
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