### Godot version

4.0beta12

### System information

all

### Issue description

In `extension_api.json` we have some function that uses parameter typed after a global enum and display it as a bitfield:
```js
{
	"name": "set_button_mask",
	"is_const": false,
	"is_vararg": false,
	"is_static": false,
	"is_virtual": false,
	"hash": 3950145251,
	"arguments": [
		{
			"name": "mask",
			"type": "bitfield::MouseButtonMask" // bitfield prefix here !
		}
	]
},
```

However the global enum's own definition doesn't mention it is a bitfield:
```js
{
	"name": "MouseButtonMask",
	// No "bitfield" field here !
	"values": [
		{
			"name": "MOUSE_BUTTON_MASK_LEFT",
			"value": 1
		},
		{
			"name": "MOUSE_BUTTON_MASK_RIGHT",
			"value": 2
		},
		{
			"name": "MOUSE_BUTTON_MASK_MIDDLE",
			"value": 4
		},
		{
			"name": "MOUSE_BUTTON_MASK_MB_XBUTTON1",
			"value": 128
		},
		{
			"name": "MOUSE_BUTTON_MASK_MB_XBUTTON2",
			"value": 256
		}
	]
},
```

On the other hand, the non-global enums (i.e. the ones defined as part of a class) have this `is_bitfield` field.
So I guess we should add it to global enum too.

### Steps to reproduce

n/a

### Minimal reproduction project

n/a
REAL_MEMBER_OFFSET(Variant::VECTOR3, "z"),
			
			INT32_MEMBER_OFFSET(Variant::VECTOR3I, "x"),
			INT32_MEMBER_OFFSET(Variant::VECTOR3I, "y"),
			INT32_MEMBER_OFFSET(Variant::VECTOR3I, "z"),
			
			REAL_BASED_BUILTIN_MEMBER_OFFSET(Variant::TRANSFORM2D, "x", "Vector2", 2),
			REAL_BASED_BUILTIN_MEMBER_OFFSET(Variant::TRANSFORM2D, "y", "Vector2", 2),
			REAL_BASED_BUILTIN_MEMBER_OFFSET(Variant::TRANSFORM2D, "origin", "Vector2", 2),
			
			REAL_MEMBER_OFFSET(Variant::VECTOR4, "x"),
			REAL_MEMBER_OFFSET(Variant::VECTOR4, "y"),
			REAL_MEMBER_OFFSET(Variant::VECTOR4, "z"),
			REAL_MEMBER_OFFSET(Variant::VECTOR4, "w"),
			
			INT32_MEMBER_OFFSET(Variant::VECTOR4I, "x"),
			INT32_MEMBER_OFFSET(Variant::VECTOR4I, "y"),
			INT32_MEMBER_OFFSET(Variant::VECTOR4I, "z"),
			INT32_MEMBER_OFFSET(Variant::VECTOR4I, "w"),
			
			REAL_BASED_BUILTIN_MEMBER_OFFSET(Variant::PLANE, "normal", "Vector3", vec3_elems),
			REAL_MEMBER_OFFSET(Variant::PLANE, "d"),
			
			REAL_MEMBER_OFFSET(Variant::QUATERNION, "x"),
			REAL_MEMBER_OFFSET(Variant::QUATERNION, "y"),
			REAL_MEMBER_OFFSET(Variant::QUATERNION, "z"),
			REAL_MEMBER_OFFSET(Variant::QUATERNION, "w"),
			
			REAL_BASED_BUILTIN_MEMBER_OFFSET(Variant::AABB, "position", "Vector3", vec3_elems),
			REAL_BASED_BUILTIN_MEMBER_OFFSET(Variant::AABB, "size", "Vector3", vec3_elems),