Add [DebuggerTypeProxy] to generated quantities (#1390)

```
/// <summary>
///     Serves as a debug display proxy for a quantity, providing a convenient way to view various components of the
///     quantity during debugging.
/// </summary>
/// <remarks>
///     This struct provides a structured view of a quantity's components such as abbreviation, unit, value, and convertor
///     during debugging.
///     Each component is represented by a nested struct, which can be expanded in the debugger to inspect its properties.
/// </remarks>
internal readonly struct QuantityDisplay(IQuantity quantity)
```
This is added to all quantities such:
```
    [DataContract]
    [DebuggerTypeProxy(typeof(QuantityDisplay))]
    public readonly partial struct Mass :
```
There are 4 properties visible, each of which can be further expanded:

1. `Abbreviation`: displays the `DefaultAbbreviation` and expands with
the list all abbreviations for the current unit, also holds a property
with the possible unit conversions (displaying the target abbreviation
in the `ConvertedQuantity[]`)
2. `Unit`: displays the `Unit` such as `Milligram` and expands to the
list of other options, where every other options expands to the
respective `ConvertedQuantity` (much like a _smart enum_).
3. `Value`: displays the `DoubleValue` by default and expands with the
`IsDecimal`, `DecimalValue` and `DoubleValue` properties
4. `ValueConversions`: displays the output of the `QuantityToString` by
default and expands with the list of possible QuantityToString options
(currently only has the `GeneralFormat` and `ShortFormat` properties) as
well as the list of possible unit conversions (`ConvertedQuantity[]`)

Note that I've had to carefully pick the property names such that they
are sorted (more or less) how I wanted, as visual studio sorts them
alphabetically, not by the order of declaration. Perhaps there (is /
would one day be) an option to change that behavior but, yeah- that's it
for now.

I've only tested this with Visual Studio 2022 - but i don't see why
there should by any issues with the other IDEs. I did observe that not
all things are always displayed on net48 (sometimes there is the
_"..requires thread to complete..").


![image](https://github.com/angularsen/UnitsNet/assets/5253184/3569a22b-de5e-46a3-853f-969d0ee3763c)

![image](https://github.com/angularsen/UnitsNet/assets/5253184/73aa6751-3cdf-4d30-a451-7a486550c3bd)

![image](https://github.com/angularsen/UnitsNet/assets/5253184/b6570b4c-f552-40b9-9fc8-62717712aa62)

![image](https://github.com/angularsen/UnitsNet/assets/5253184/5c49f049-2d99-4e87-b938-38b090ef5f98)

![image](https://github.com/angularsen/UnitsNet/assets/5253184/4ebc3c79-6518-4dd3-8dfd-e5ddb69b884f)

If we open the visualizer view with the list from the `QuantityToUnit`
we get a nice little table:


![image](https://github.com/angularsen/UnitsNet/assets/5253184/48a100b8-02be-4283-b2e1-5a0537717ccd)

Author: lipchev

CodeGen/Generators/UnitsNetGen/QuantityGenerator.cs

@@ -37,6 +37,7 @@ public string Generate()
             Writer.WL(GeneratedFileHeader);
             Writer.WL(@"
 using System;
+using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
 using System.Globalization;
 using System.Linq;
@@ -64,6 +65,7 @@ namespace UnitsNet
             Writer.WLIfText(1, GetObsoleteAttributeOrNull(_quantity));
             Writer.WL(@$"
     [DataContract]
+    [DebuggerTypeProxy(typeof(QuantityDisplay))]
     public readonly partial struct {_quantity.Name} :
         {(_quantity.GenerateArithmetic ? "IArithmeticQuantity" : "IQuantity")}<{_quantity.Name}, {_unitEnumName}, {_quantity.ValueType}>,");