feat(clrcore): add implicit conversion from int to CString in Player

[geofmigliacci]

Goal of this PR

This PR adds an implicit conversion from int to CString in the Player class as a quality of life (QoL) improvement on the server side. This allows for direct conversion without the need to explicitly call Handle.ToString().

See : thorium-cfx/mono_v2_get_started#37

It might be interesting to add this implicit conversion to other entities as well.

How is this PR achieving the goal

This PR adds an implicit operator CString(Player player).
With this change, you can now do the following:

Player p1 = new Player(1);
Natives.ThisCoolNative(p1, "hello", 1234); // ThisCoolNative(CString, CString, int)

This PR applies to the following area(s)

Server, ScRT: C#

Successfully tested on

Game builds: Latest

Platforms: Windows

Checklist

• Code compiles and has been tested successfully.
• Code explains itself well and/or is documented.
• My commit message explains what the changes do and what they are for.
• No extra compilation warnings are added by these changes.

Fixes issues

resolves thorium-cfx/mono_v2_get_started#37