Use forward declaration for VFS::Manager

components/esm4/reader.cpp

@@ -41,6 +41,7 @@
 #include <components/files/conversion.hpp>
 #include <components/misc/strings/lower.hpp>
 #include <components/to_utf8/to_utf8.hpp>
+#include <components/vfs/manager.hpp>
 
 #include "grouptype.hpp"
 

components/esm4/reader.hpp

@@ -36,13 +36,17 @@
 
 #include <components/esm/formid.hpp>
 #include <components/files/istreamptr.hpp>
-#include <components/vfs/manager.hpp>
 
 namespace ToUTF8
 {
     class StatelessUtf8Encoder;
 }
 
+namespace VFS
+{
+    class Manager;
+}
+
 namespace ESM4
 {
 #pragma pack(push, 1)