[oatpp] build failure with MSVC and manifest mode

@Cheney-W is already working on this.

Since May 30, 2025.

### Operating system

Windows

### Compiler

MSVC

### Steps to reproduce the behavior

```Shell
1. Create console c++ application in Visual Studio and enable manifest mode.
2. Add oatpp to vcpkg.json deps
3. Include any header from oatpp (I think this is part of the issue as the include shows up as oatpp-1.3.0/oatpp/oatpp/...)

4. Compile
```

### Failure logs

```
0>WindowsServiceManagerApi.obj: Error LNK2019 : unresolved external symbol "public: static class std::shared_ptr __cdecl oatpp::web::server::HttpRouter::createShared(void)" (?createShared@HttpRouter@server@web@oatpp@@SA?AV?$shared_ptr@VHttpRouter@server@web@oatpp@@@std@@XZ) referenced in function main
0>WindowsServiceManagerApi.exe: Error LNK1120 fatal: 1 unresolved externals
0>------- Finished building project: WindowsServiceManagerApi. Succeeded: False. Errors: 2. Warnings: 0
```

### Additional context

```
#include
#include

int main()
{
auto router = oatpp::web::server::HttpRouter::createShared();
std::cout << "Hello World!\n";
}
```

My assumption is this was tested only with CMake builds?