feat: add WordPress as runtime — Dockerfile, K8s env vars, wp-content PVC, frontend UI

Backend:
- Add WORDPRESS to AppRuntime enum
- Add wordpressDockerfile() using wordpress:6-php8.3-apache base image
  with custom theme/plugin/wp-content merge support
- Add WordPress-specific K8s env vars (WORDPRESS_DB_HOST, WORDPRESS_DB_USER,
  WORDPRESS_DB_PASSWORD, WORDPRESS_DB_NAME, WORDPRESS_TABLE_PREFIX)
- Create wp-content PersistentVolumeClaim (2Gi) for WordPress deployments
- Mount wp-content PVC in deployment container at /var/www/html/wp-content

Frontend:
- Add 'wordpress' to runtime type unions (Application, CreateApplicationDto)
- Add WordPress runtime card in deploy page (port 80, blue icon)
- Auto-select MySQL database when WordPress is chosen, disable other DB options
- Show Persian hint 'وردپرس به MySQL نیاز دارد' when WordPress selected
- Update all runtime icon colors across dashboard, apps, admin/apps pages
  to show blue-600 for WordPress

frontend/src/app/dashboard/apps/[id]/page.tsx

@@ -358,7 +358,7 @@ export default function AppDetailPage() {
       <div className="flex flex-col sm:flex-row sm:items-center gap-4">
         <div className="flex items-center gap-4 flex-1 min-w-0">
           <div className="w-14 h-14 rounded-2xl bg-primary-50 flex items-center justify-center shrink-0">
-            <Hexagon className={`w-7 h-7 ${app.runtime === 'nodejs' ? 'text-green-500' : 'text-orange-500'}`} />
+            <Hexagon className={`w-7 h-7 ${app.runtime === 'nodejs' ? 'text-green-500' : app.runtime === 'wordpress' ? 'text-blue-600' : 'text-orange-500'}`} />
           </div>
           <div className="min-w-0">
             <div className="flex items-center gap-2 flex-wrap">

frontend/src/app/dashboard/apps/page.tsx

@@ -101,7 +101,7 @@ export default function AppsPage() {
                       <td className="px-6 py-4">
                         <Link href={`/dashboard/apps/${app.id}`} className="flex items-center gap-3 group">
                           <div className="w-9 h-9 rounded-lg bg-primary-50 flex items-center justify-center shrink-0">
-                            <Hexagon className={`w-5 h-5 ${app.runtime === 'nodejs' ? 'text-green-600' : 'text-orange-500'}`} />
+                            <Hexagon className={`w-5 h-5 ${app.runtime === 'nodejs' ? 'text-green-600' : app.runtime === 'wordpress' ? 'text-blue-600' : 'text-orange-500'}`} />
                           </div>
                           <span className="font-semibold text-gray-900 group-hover:text-primary-600 transition-colors">
                             {app.name}
@@ -149,7 +149,7 @@ export default function AppsPage() {
                   <div className="flex items-center justify-between mb-3">
                     <div className="flex items-center gap-3">
                       <div className="w-10 h-10 rounded-xl bg-primary-50 flex items-center justify-center">
-                        <Hexagon className={`w-5 h-5 ${app.runtime === 'nodejs' ? 'text-green-600' : 'text-orange-500'}`} />
+                        <Hexagon className={`w-5 h-5 ${app.runtime === 'nodejs' ? 'text-green-600' : app.runtime === 'wordpress' ? 'text-blue-600' : 'text-orange-500'}`} />
                       </div>
                       <div>
                         <h3 className="font-semibold text-gray-900">{app.name}</h3>