Upgrade Raylib to 6.0 (#337)

* Updated target to Raylib 6 + synced invoke called with the changes in C. [WARNING: Breaking changes!]

* Added severial examples. Corrected towards the correct return type and add utilities to prevent working with pointers

* Additional resources from the Raylib repo.

* Fixed additional pinvokes to match with the new raylib bindings. [Warning breaking changes!]

* Fixing the QOL utils

* Fixing the Mesh struct

* Applying changes after review. Merged resources.LICENSE + raylib-cs.Native.csproj only targets dotnet8

* Updated README to reflect .NET 10 and Raylib 6 compatibility changes.

* Updated shader colors, adjusted car model scale, disabled HDR in SkyboxDemo, and fixed camera mode assignment. Removed unused `Capacity` field in FilePathList struct.

* Improved XML comments for consistency, fixed spacing and formatting across examples, added new resources to `resources.LICENSE`.

* Updated XML comment for `GetDirectoryFileCountEx` to clarify behavior and filtering options.

* Updated and clarified XML comments for methods and parameters, improved naming consistency, and refined shader-related functions. Renamed enums in `Shader.cs` for so it is inline with the upstream.

* Improved XML comments for clarity and consistency in `Model.cs` and `Mesh.cs`, updated method and variable names for better readability, and adjusted logic in span creation methods.

* Corrected XML comment capitalization in `Model.cs`.

---------

Co-authored-by: Meatcorps <info@meatcorps.nl>

Raylib-cs/types/native/FilePathList.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Runtime.InteropServices;
 
 namespace Raylib_cs;
@@ -8,11 +9,6 @@ namespace Raylib_cs;
 [StructLayout(LayoutKind.Sequential)]
 public unsafe struct FilePathList
 {
-    /// <summary>
-    /// Filepaths max entries
-    /// </summary>
-    public uint Capacity;
-
     /// <summary>
     /// Filepaths entries count
     /// </summary>

Raylib-cs/types/native/Utf8Buffer.cs

@@ -21,6 +21,11 @@ public readonly ref struct Utf8Buffer
         return (sbyte*)_data.ToPointer();
     }
 
+    public unsafe byte* AsBytePointer()
+    {
+        return (byte*)_data.ToPointer();
+    }
+
     public void Dispose()
     {
         Marshal.ZeroFreeCoTaskMemUTF8(_data);