feat(all): add game SDK and harden client login and game rules

- Add costume burst upgrades with durable replay and fix permanent SR equipment gacha.
- Add server game.json rules for optional collaboration UR weapons, with packaging and documentation.
- Add GameNames/GameSdk NuGet tooling, readable types, reobfuscation, complete source/PDB navigation and shared-runtime installation.
- Split plugin responsibilities, prefer typeof/nameof, centralize MSBuild settings and ignore local paths; remove the unused LoginUI test project.
- Fix login recovery and TLS through native platform HTTP and a private game relay; read device region directly from the OS time zone.

Validation: go test ./... -count=1, go vet ./..., plugin Release builds, SDK/runtime self-tests, Roslyn embedded-source navigation, gofmt check and git diff --check.

plugins/LocalIdentity/LocalIdentity.csproj

@@ -6,12 +6,7 @@
     <AssemblyName>BD2LocalIdentity</AssemblyName>
     <RootNamespace>Bd2LocalIdentity</RootNamespace>
     <BD2PluginVersionKey>local_identity</BD2PluginVersionKey>
-    <BD2ManagedDir Condition="'$(BD2ManagedDir)' == ''">$(GameDir)\BrownDust II_Data\Managed</BD2ManagedDir>
-    <BD2BepInExDir Condition="'$(BD2BepInExDir)' == ''">$(GameDir)\BepInEx</BD2BepInExDir>
   </PropertyGroup>
-  <Target Name="RequireGameDir" BeforeTargets="ResolveReferences" Condition="'$(GameDir)' == ''">
-    <Error Text="GameDir is required. Build with -p:GameDir=&lt;local-client-directory&gt;." />
-  </Target>
   <ItemGroup>
     <Reference Include="BepInEx">
       <HintPath>$(BD2BepInExDir)\core\BepInEx.dll</HintPath>
@@ -34,5 +29,4 @@
       <Private>false</Private>
     </Reference>
   </ItemGroup>
-  <Import Project="..\VersionSource.targets" />
 </Project>