Add support for sound backends & some miniaudio changes (#4978)

Miniaudio now runs everything in a separate audio thread - this uses boost::asio's io_context.
Our miniaudio implementation is now also much simplified - it does not use its own resource manager or device. This might end up being stupid if sounds don't work after changing output device or locking or w/e
I've made the sound controller into an interface, meaning we can support multiple sound backends in Chatterino. I've added a Null sound backend that disables all sound. A QMediaPlayer or QSoundEffect or Qt backend could be added.
Miniaudio might idle & disable the device now too, not sure

I've added some unrelated changes in the form of a new setting type, and a new setting page helper function for it, which will hopefully make adding new enum settings easier in the future.
This setting stores its value as a string instead of an int, and uses magic_enum to convert between that string value and its enum value.

src/widgets/settingspages/GeneralPage.cpp

@@ -5,6 +5,7 @@
 #include "common/Version.hpp"
 #include "controllers/hotkeys/HotkeyCategory.hpp"
 #include "controllers/hotkeys/HotkeyController.hpp"
+#include "controllers/sound/ISoundController.hpp"
 #include "providers/twitch/TwitchChannel.hpp"
 #include "providers/twitch/TwitchIrcServer.hpp"
 #include "singletons/Fonts.hpp"
@@ -20,6 +21,7 @@
 #include "widgets/settingspages/GeneralPageView.hpp"
 #include "widgets/splits/SplitInput.hpp"
 
+#include <magic_enum.hpp>
 #include <QDesktopServices>
 #include <QFileDialog>
 #include <QFontDialog>
@@ -1134,6 +1136,14 @@ void GeneralPage::initLayout(GeneralPageView &layout)
         "Show a Send button next to each split input that can be "
         "clicked to send the message");
 
+    auto *soundBackend = layout.addDropdownEnumClass<SoundBackend>(
+        "Sound backend (requires restart)",
+        magic_enum::enum_names<SoundBackend>(), s.soundBackend,
+        "Change this only if you're noticing issues with sound playback on "
+        "your system",
+        {});
+    soundBackend->setMinimumWidth(soundBackend->minimumSizeHint().width());
+
     layout.addStretch();
 
     // invisible element for width

src/widgets/settingspages/GeneralPageView.hpp

@@ -247,6 +247,51 @@ public:
         return combo;
     }
 
+    template <typename T, std::size_t N>
+    ComboBox *addDropdownEnumClass(const QString &text,
+                                   const std::array<std::string_view, N> &items,
+                                   EnumStringSetting<T> &setting,
+                                   QString toolTipText,
+                                   const QString &defaultValueText)
+    {
+        auto *combo = this->addDropdown(text, {}, std::move(toolTipText));
+
+        for (const auto &text : items)
+        {
+            combo->addItem(QString::fromStdString(std::string(text)));
+        }
+
+        if (!defaultValueText.isEmpty())
+        {
+            combo->setCurrentText(defaultValueText);
+        }
+
+        setting.connect(
+            [&setting, combo](const QString &value) {
+                auto enumValue =
+                    magic_enum::enum_cast<T>(value.toStdString(),
+                                             magic_enum::case_insensitive)
+                        .value_or(setting.defaultValue);
+
+                auto i = magic_enum::enum_integer(enumValue);
+
+                combo->setCurrentIndex(i);
+            },
+            this->managedConnections_);
+
+        QObject::connect(
+            combo, &QComboBox::currentTextChanged,
+            [&setting](const auto &newText) {
+                // The setter for EnumStringSetting does not check that this value is valid
+                // Instead, it's up to the getters to make sure that the setting is legic - see the enum_cast above
+                // You could also use the settings `getEnum` function
+                setting = newText;
+                getApp()->windows->forceLayoutChannelViews();
+            });
+
+        return combo;
+    }
+
     DescriptionLabel *addDescription(const QString &text);
 
     void addSeperator();