Inventory/host_vars cleanup.

- hosts: remove gw-replacement2/3.local.netz and k1371.dyndns.org
  (duplicate of gw-ak.oopen.de).
- host_vars: move obsolete host directories to host_vars/DELETED/
  (devel-cloud, file-blkr-alt, file-ipa, ga-campus-gw-temp, ga-st-mm,
  gitea.so36.net, nc-gw, moodle, nscache, server16, server20, web-test,
  gw-replacement2/3/4).
- host_vars: fix file names (ga-al-gw-common.yml,
  gw-replacement.local.netz/gw-replacement-common.yml) and the header of
  mm-nd-test-ipt-server.yml.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

host_vars/mm-nd-test.oopen.de/mm-nd-test-ipt-server.yml

@@ -1,9 +1,9 @@
 ---
-# ipt-firewall configuration for a.ns.oopen.de
+# ipt-firewall configuration for mm-nd-test.oopen.de
 # Generated by extract-fw-host-vars.py - review before committing!
-# Place in: host_vars/<hostname>/ipt_firewall.yml
+# Place in: host_vars/<hostname>/<short-hostname>-ipt-server.yml
 
-fw_manage_config: true
+fw_manage_config: false
 
 # --- Network
 fw_ext_interfaces: