When the C# bindings generator finds a type without meta assume the type
refers to the 64-bit version of the type:
- `float` is converted to `double`
- `int` is converted to `long`
Vector4 and Vector4i were implemented incorrectly in godot_variant.
They were also missing their respective Variant conversion callbacks
(used for generic collections).
Took the chance to remove unnecessary native calls for creating
Variant from Vector4, as now it can be done from C# (which is faster).
- Use different syntax for object printing to avoid confusion with arrays.
- Print null as `<null>` to avoid confusion with a string `"null"`.
- Display `<empty>` in editor resource pickers to avoid confusion
with array-based properties.
- Fix platform detection after Linux OS name was renamed from `LinuxBSD`
to `Linux`
- Fix arch detection after renaming `64` to `x86_64`
- Fix typo in `find_hostfxr`
- Replace `IndexOutOfRangeException` with `ArgumentOutOfRangeException`
- Replace `Exception` with a more specific exception
- Add the parameter name to argument exception
- Update documentation for methods that throw exceptions
- Use `StringBuilder` to build exception messages
- Ensure exception messages end with a period
`libnethost.a` detection failed on my Linux system (Mageia 9, using Fedora 36
dotnet repos), because it used the first match which isn't the one matching
the rest of the SDK:
```
$ dotnet --list-runtimes
Microsoft.AspNetCore.App 3.1.28 [/usr/share/dotnet/shared/Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 6.0.8 [/usr/share/dotnet/shared/Microsoft.AspNetCore.App]
Microsoft.NETCore.App 3.1.28 [/usr/share/dotnet/shared/Microsoft.NETCore.App]
Microsoft.NETCore.App 6.0.5 [/usr/share/dotnet/shared/Microsoft.NETCore.App]
Microsoft.NETCore.App 6.0.8 [/usr/share/dotnet/shared/Microsoft.NETCore.App]
```
No idea why I still have 6.0.5 installed but it should pick the highest I guess.
- Remove event as a valid target of `SignalAttribute`
- Stop adding the `[Signal]` attribute to events in bindings_generator
- Make bindings_generator use the `EventHandler` suffix to be consistent with the C# source generator
- Remove obsolete comment about the signal's delegate name
