* Remove unused `EditorPropertyMember` and related hints, previouly used by
VisualScript. Such logic should be implemented in the VS module itself.
* As the above broke compatibility with the VS module, clean up the other
hacks that were still in core in support of VisualScript.
* `PROPERTY_USAGE_INTERNATIONALIZED` was only used in Object's
`get_translatable_strings()`, which is a legacy function not used anywhere.
So both are removed.
* Reordered some usage flags after the above removal to minimize the diff.
* General clean up.
Fixes#30203.
Co-authored-by: Rémi Verschelde <rverschelde@gmail.com>
Changed the signal declaration signal to:
```
// The following generates a MySignal event
[Signal] public delegate void MySignalEventHandler(int param);
```
The editor no longer needs to create temporary instances to get the
default values. The initializer values of the exported properties are
still evaluated at runtime. For example, in the following example,
`GetInitialValue()` will be called when first looks for default values:
```
[Export] int MyValue = GetInitialValue();
```
Exporting fields with a non-supported type now results in a compiler
error rather than a runtime error when the script is used.
