feat: Cleans up UOP file handling. Adds automatic bounds.bin generation (#1744)

### Summary
* Unifies reading UOP File indexes
* Adds ArtData file reader to get graphic bounds
* Automatically generates Bounds.bin from art file if missing
* Adds [GenBounds command to regenerate the bounds.bin file. Useful for when the art file changes.

Projects/Server.Tests/Tests/Gumps/TestGumps/StaticLayoutTestGump.cs

@@ -1,4 +1,3 @@
-using System;
 using Server.Gumps;
 
 namespace Server.Tests.Gumps;