fix: Missing includes when building with `USE_PRECOMPILED_HEADERS=OFF`

[brian6932]

Fixes the following build errors with -DUSE_PRECOMPILED_HEADERS=OFF on Windows.

TitlebarButtons.hpp

``` src\widgets/helper/TitlebarButtons.hpp(13): error C2504: 'QObject': base class undefined src\widgets\helper\TitlebarButtons.cpp(16): error C2614: 'chatterino::TitleBarButtons': illegal member initialization: 'QObject' is not a base or member ```

AttachToConsole.cpp

``` src\util\AttachToConsole.cpp(16): error C2065: 'stdout': undeclared identifier src\util\AttachToConsole.cpp(16): error C3861: 'freopen_s': identifier not found src\util\AttachToConsole.cpp(16): error C2678: binary '=': no operator found which takes a left-hand operand of type 'const std::_Ignore' (or there is no acceptable conversion) C:\Program Files (x86)\Microsoft Visual Studio\2022\BuildTools\VC\Tools\MSVC\14.39.33519\include\tuple(129): note: could be 'std::_Ignore &std::_Ignore::operator =(std::_Ignore &&)' src\util\AttachToConsole.cpp(16): note: 'std::_Ignore &std::_Ignore::operator =(std::_Ignore &&)': cannot convert 'this' pointer from 'const std::_Ignore' to 'std::_Ignore &' src\util\AttachToConsole.cpp(16): note: Conversion loses qualifiers C:\Program Files (x86)\Microsoft Visual Studio\2022\BuildTools\VC\Tools\MSVC\14.39.33519\include\tuple(129): note: or 'std::_Ignore &std::_Ignore::operator =(const std::_Ignore &)' src\util\AttachToConsole.cpp(16): note: 'std::_Ignore &std::_Ignore::operator =(const std::_Ignore &)': cannot convert 'this' pointer from 'const std::_Ignore' to 'std::_Ignore &' src\util\AttachToConsole.cpp(16): note: Conversion loses qualifiers C:\Program Files (x86)\Microsoft Visual Studio\2022\BuildTools\VC\Tools\MSVC\14.39.33519\include\tuple(125): note: or 'const std::_Ignore &std::_Ignore::operator =(const _Ty &) noexcept const' src\util\AttachToConsole.cpp(16): note: Failed to specialize function template 'const std::_Ignore &std::_Ignore::operator =(const _Ty &) noexcept const' src\util\AttachToConsole.cpp(16): note: With the following template arguments: src\util\AttachToConsole.cpp(16): note: '_Ty=unknown-type' src\util\AttachToConsole.cpp(16): note: while trying to match the argument list '(const std::_Ignore, unknown-type)' src\util\AttachToConsole.cpp(17): error C2065: 'stderr': undeclared identifier src\util\AttachToConsole.cpp(17): error C3861: 'freopen_s': identifier not found src\util\AttachToConsole.cpp(17): error C2678: binary '=': no operator found which takes a left-hand operand of type 'const std::_Ignore' (or there is no acceptable conversion) C:\Program Files (x86)\Microsoft Visual Studio\2022\BuildTools\VC\Tools\MSVC\14.39.33519\include\tuple(129): note: could be 'std::_Ignore &std::_Ignore::operator =(std::_Ignore &&)' src\util\AttachToConsole.cpp(17): note: 'std::_Ignore &std::_Ignore::operator =(std::_Ignore &&)': cannot convert 'this' pointer from 'const std::_Ignore' to 'std::_Ignore &' src\util\AttachToConsole.cpp(17): note: Conversion loses qualifiers C:\Program Files (x86)\Microsoft Visual Studio\2022\BuildTools\VC\Tools\MSVC\14.39.33519\include\tuple(129): note: or 'std::_Ignore &std::_Ignore::operator =(const std::_Ignore &)' src\util\AttachToConsole.cpp(17): note: 'std::_Ignore &std::_Ignore::operator =(const std::_Ignore &)': cannot convert 'this' pointer from 'const std::_Ignore' to 'std::_Ignore &' src\util\AttachToConsole.cpp(17): note: Conversion loses qualifiers C:\Program Files (x86)\Microsoft Visual Studio\2022\BuildTools\VC\Tools\MSVC\14.39.33519\include\tuple(125): note: or 'const std::_Ignore &std::_Ignore::operator =(const _Ty &) noexcept const' src\util\AttachToConsole.cpp(17): note: Failed to specialize function template 'const std::_Ignore &std::_Ignore::operator =(const _Ty &) noexcept const' src\util\AttachToConsole.cpp(17): note: With the following template arguments: src\util\AttachToConsole.cpp(17): note: '_Ty=unknown-type' src\util\AttachToConsole.cpp(17): note: while trying to match the argument list '(const std::_Ignore, unknown-type)' ```