Add empty test level and Unreal MCP tooling

- L_TestFlight: empty, zero-gravity level for Phase 0 flight testing,
  set as editor/game default map.
- Enable UnrealMCPython + Python Editor Script Plugin, third-party
  MCP plugin (GenOrca/unreal-mcp v2.2.0) giving direct editor control
  (actors, blueprints, levels, materials, etc.) alongside Epic's
  built-in Unreal MCP plugin.
- Vendor the mcp-server Python source used to bridge to the plugin.
- .mcp.json intentionally gitignored (machine-specific absolute paths).

SpaceGame.uproject

@@ -10,6 +10,21 @@
 			"TargetAllowList": [
 				"Editor"
 			]
+		},
+		{
+			"Name": "ModelContextProtocol",
+			"Enabled": true,
+			"TargetAllowList": [
+				"Editor"
+			]
+		},
+		{
+			"Name": "PythonScriptPlugin",
+			"Enabled": true
+		},
+		{
+			"Name": "UnrealMCPython",
+			"Enabled": true
 		}
 	]
 }