fix: update to .NET 8, fix Persistence.S3 build

- Update global.json SDK version from 8.0.100-preview to 8.0.418
- Update Persistence.S3 target framework from net5.0 to net8.0
- Add AWSSDK.S3 NuGet package reference
- Add missing AWS using directives in S3Storage.cs

Author: Airwin

src/BrowserGameEngine.Persistence.S3/BrowserGameEngine.Persistence.S3.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>net8.0</TargetFramework>
     <LangVersion>preview</LangVersion>
     <Nullable>enable</Nullable>
   </PropertyGroup>
@@ -10,4 +10,8 @@
     <ProjectReference Include="..\BrowserGameEngine.Persistence\BrowserGameEngine.Persistence.csproj" />
   </ItemGroup>
 
+  <ItemGroup>
+    <PackageReference Include="AWSSDK.S3" Version="4.0.18.6" />
+  </ItemGroup>
+
 </Project>

src/BrowserGameEngine.Persistence.S3/S3Storage.cs

@@ -1,5 +1,7 @@
 using System;
 using System.Threading.Tasks;
+using Amazon;
+using Amazon.S3;
 
 namespace BrowserGameEngine.Persistence.S3 {
 	public class S3Storage : IBlobStorage {

src/global.json

@@ -1,5 +1,6 @@
 {
   "sdk": {
-    "version": "8.0.100-preview.7.23376.3"
+    "version": "8.0.418",
+    "rollForward": "latestMinor"
   }
 }