[Xon] Proxy Link-Forum 2.5.0

• Require StandardLib v1.21.0+
• XF2.3 support
• php 8.3 compatibility fix

• Fix "LogicException: Must provide at least 1 metadata value" when a crafted search url using a non-existent forum

• Reduce number of joins when fetching proxied forum data
• Make proxy link forums excluded from XF permission building, and push view check to proxied forum/category.
  This eliminates the overhead on permission rebuilding on adding proxy link forums to the node-tree.
• Known issue of disabling a proxy link forum from proxying doesn't cause permissions to be rebuild for the node.

• Remove unused template modification
• Fix proxied forums/categories did not display stats from the sub-forums of the proxied forum/category

• Require php 7.2
• XenForo 2.2+
• Add per-link-forum "Include proxied forum in search results" option (default true)
• Fix "Search sub-forums as well" did not include proxied forums/categories

• Fix template error on node list page when marking a link proxy forum as a proxy

• Fully remove XF2.0 support
• Proxied node stats are now correctly propagated
• Add category support, thanks @Lukas W.

Compatibility fix for ElasticSearch Essentials auto-complete when Gift Upgrades is also installed

XenForo 2.2.4 compatibility update

Compatibility fix for ElasticSearch Essentials auto-complete when Gift Upgrades is also installed