🐛 Move Openfire auth module under rootfs/usr (AI.md rule 9) 🐛

- docker/rootfs/usr/local/share/prosody-plugins/mod_auth_openfire_hybrid.lua: moved from docker/rootfs/prosody-plugins-contrib/ (rootfs top level may only hold root/, tmp/, usr/)
- docker/rootfs/usr/local/bin/entrypoint.sh: add /usr/local/share/prosody-plugins to plugin_paths

docker/rootfs/usr/local/bin/entrypoint.sh

@@ -180,7 +180,7 @@ network_settings = {
 data_path = "/config/data";
 
 -- Plugin paths
-plugin_paths = { "/prosody-plugins-custom", "/prosody-plugins/", "/prosody-plugins-contrib" };
+plugin_paths = { "/prosody-plugins-custom", "/prosody-plugins/", "/prosody-plugins-contrib", "/usr/local/share/prosody-plugins" };
 
 Include "conf.d/*.cfg.lua"
 MAIN_CFG