[TRACKER] GDScript `class_name`

[adamscott]

Issues

• Using class_name in a newly created script does not register it in the node creation dialog, if under addons/ (unless part of an enabled editor plugin) #30048
• Shadows a native class error doesn't appear for class_name Engine #48311
• Renaming gdscript with class_name can cause cyclic error. #56628
• Custom class nodes break when changing inheritance #81222
• class_name classes become invalid on PCK scenes when unloading PCK files #82479
• Class Name is lost when creating new one by duplicating existing script #83395
• take_over_path and extending the same named class twice #83542
• Class names suddenly seen as invalid #83561
• class_name not loading(can not be accessed, here from other code) but loads after Deleting the line and retyping after few seconds.  #90240
• "Class hides a global script class" script parsing issue #94378
• Dynamic GDScript cannot resolve class_name in script #98985

Some issues brought up by class_name

• Addon authors avoid them because of possible naming conflicts.
• In some cases, scripts with preload() via transitive dependencies can load a lot of the project resources.
• Global classes clutters the node/resource creation dialog.
  • Implement hidden class in ScriptServer to replace EditorX class being hidden. #91020
  • Add is_internal property to scripts to hide objects from create dialog #95806
• There are no namespaces.

Many thanks to @dalexeev for the list.