Fix extension soft lock when inspecting Dictionary variables with Variant key types

[pminiszewski]

Hello,

In some cases the extension would soft lock making it impossible to inspect variables. The symptoms are very similar to #699, except this time the problem is caused by typed dictionaries that have Variant as a value type.

To reproduce try setting a breakpoint in the script below and inspecting contents of my_dict.
The issue replicates on Godot 4.4 (and possibly newer versions) on both Windows and MacOs.

extends Node

func _ready() -> void:
    var my_dict: Dictionary[int, Variant] = {5: "abc", 31: "Vector3(5, 6, 7)", 63: "xyzW"}
    print("")

The solution is to container check type flags and then decode type info only if flag is nonzero. If flag === 0 then there will be no type information included in the buffer.

[DaelonSuzuka]

This looks fine to me. Thanks for investigating this and contributing!