feat: net10.0 Linux Console mode — zero Mono, 0 compile errors

Migrated from net48 (.NET Framework) to net10.0 (cross-platform):
- All 14 csproj: net48 → net10.0, WindowsDesktop SDK → Microsoft.NET.Sdk
- Excluded WinForms files (Form/**, DebugControl, GameControl, etc.)
- Excluded DB modules (GameDAL db/Sql/**, MrWu DB files)
- Excluded server runtime files (GameBase, GlobalSever managers, GameNetModule stubs)
- Added minimal stubs (GameDoStub.cs, NamespaceStubs.cs, ServerCoreStubs.cs)
- Created hjha-console entry project
- Fixed hardcoded Windows path → ./test/ directory
- Updated global.json to SDK 10.0.109

Console test mode: PdkGameMain(null).Test() → 发牌→包庄→打牌→结算
Verified: dotnet build 0 errors, dotnet run outputs game state machine

NetWorkMessage/NetWorkMessage.csproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFramework>net48</TargetFramework>
+    <TargetFramework>net10.0</TargetFramework>
     <OutputType>Library</OutputType>
     <RootNamespace>NetWorkMessage</RootNamespace>
     <AssemblyName>NetWorkMessage</AssemblyName>