feat: 迁入 MiGu.Server、平台前端与车辆列表 reflection 回退

从 Simple-FR 拆出 Platform.Server 并重命名为 MiGu.Server；frontends 源码与构建脚本迁入本仓库。地图监控在 projection/cars 失败或为空时回退 reflection 车辆列表；Simple 仓库已移除旧 Platform.Server。

Co-authored-by: Cursor <cursoragent@cursor.com>

MiGu.Server/appsettings.Development.json

@@ -0,0 +1,17 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Information",
+      "Yarp": "Debug"
+    }
+  },
+  "SimpleLite": {
+    "Enabled": true,
+    "ExecutablePath": "E:\\Work\\Core\\Simple-FR\\Simple\\SimpleLite\\bin\\Debug\\SimpleLite.exe",
+    "WorkingDirectory": "E:\\Work\\Core\\Simple-FR\\Simple\\SimpleLite\\bin\\Debug",
+    "ProjectionPort": 8222,
+    "ReadinessTimeoutMs": 8000,
+    "FollowParent": false
+  }
+}