Installer-rework

split installer structure into systems, updated non-functional Debian12 installer with some minor fixes to Ubuntu24 installer.
Updated docs.

install/ubuntu24/netalertx.conf

@@ -0,0 +1,21 @@
+server {
+    listen 20211 default_server;
+    root /var/www/html/netalertx;
+    index index.php;
+    #rewrite /app/(.*) / permanent;
+    add_header X-Forwarded-Prefix "/netalertx" always;
+    proxy_set_header X-Forwarded-Prefix "/netalertx";
+
+  location ~* \.php$ {
+    # Set Cache-Control header to prevent caching on the first load
+    add_header Cache-Control "no-store";
+    fastcgi_pass unix:/run/php/php8.3-fpm.sock;
+    include         fastcgi_params;
+    try_files $uri =404;
+    fastcgi_param   SCRIPT_FILENAME    $document_root$fastcgi_script_name;
+    fastcgi_param   SCRIPT_NAME        $fastcgi_script_name;
+    fastcgi_connect_timeout 75;
+    fastcgi_send_timeout 600;
+    fastcgi_read_timeout 600;
+  }
+}