tools: Add CROWN_DEFAULT_SERVER_PORT

tools/config.vala

@@ -15,4 +15,6 @@ namespace Crown
 	const string EXE_SUFFIX = ".exe";
 #endif
 	const string ENGINE_EXE = EXE_PREFIX + "crown-development-64" + EXE_SUFFIX;
+
+	const uint16 CROWN_DEFAULT_SERVER_PORT = 10618;
 }