ci: workflow 移到仓库根 .gitea/workflows，路径适配 BasePlatformDotnet 子目录

Gitea Actions 仅识别仓库根 .gitea/workflows/，原 BasePlatformDotnet/.gitea/workflows/ci.yml 不触发。
- 移动到根 .gitea/workflows/ci.yml
- 所有 dotnet 命令改指 BasePlatformDotnet/yh-platform-net.sln
- 推送目标 artifacts 同步 BasePlatformDotnet/artifacts

.gitea/workflows/ci.yml

@@ -16,16 +16,16 @@ jobs:
           dotnet-version: 8.0.x
 
       - name: Restore
-        run: dotnet restore yh-platform-net.sln
+        run: dotnet restore BasePlatformDotnet/yh-platform-net.sln
 
       - name: Build
-        run: dotnet build yh-platform-net.sln --no-restore -c Release
+        run: dotnet build BasePlatformDotnet/yh-platform-net.sln --no-restore -c Release
 
       - name: Test
-        run: dotnet test yh-platform-net.sln --no-build -c Release --logger "console;verbosity=normal"
+        run: dotnet test BasePlatformDotnet/yh-platform-net.sln --no-build -c Release --logger "console;verbosity=normal"
 
       - name: Pack
-        run: dotnet pack yh-platform-net.sln --no-build -c Release -o artifacts
+        run: dotnet pack BasePlatformDotnet/yh-platform-net.sln --no-build -c Release -o BasePlatformDotnet/artifacts
 
   publish:
     # 仅主分支 push 时发版到 Nexus 私服（PR 不触发）
@@ -41,7 +41,7 @@ jobs:
           dotnet-version: 8.0.x
 
       - name: Pack
-        run: dotnet pack yh-platform-net.sln -c Release -o artifacts
+        run: dotnet pack BasePlatformDotnet/yh-platform-net.sln -c Release -o BasePlatformDotnet/artifacts
 
       - name: Push to Nexus
         # Nexus 的 NuGet 推送认证走 HTTP Basic（账号+密码），不校验 api-key；
@@ -63,4 +63,4 @@ jobs:
             </packageSourceCredentials>
           </configuration>
           EOF
-          dotnet nuget push "artifacts/*.nupkg" --source nexus-nuget --configfile nuget-push.config --api-key nexus
+          dotnet nuget push "BasePlatformDotnet/artifacts/*.nupkg" --source nexus-nuget --configfile nuget-push.config --api-key nexus