feat: Adds AdvancedSearch (XmlFind)

[kamronbatman]

Summary

Adds Advanced Search (XmlFind) using [AS command.

Notable differences from XmlFind:

• No save to file.
• No "Display from" option (might add that later).
• No advanced XmlSpawner property test syntax. Only basic property operator comparisons.
• This version will freeze your shard, but fans out to all processors just like world saves. (So it should be stupid fast, especially if you have lots of cores)
• Does not support spawn entry/type/error searching. We have a spawn search command to do that already.
• I haven't set up correct "defaults" for the options when you first open it. I'll do that later.

Screenshots