Add settings API and specification

The details of the API are in the `/docs/specsSettings-API.md` file.

The enums do not list all available settings, more are to be added as
the settings API replaces inline QSettings calls.

src/settings/settings.h

@@ -0,0 +1,93 @@
+#pragma once
+#include <string>
+
+namespace settings
+{
+enum class BoolSetting
+{
+    PLAYSPACE_lockXToggle,
+    PLAYSPACE_lockYToggle,
+    PLAYSPACE_lockZToggle,
+    PLAYSPACE_momentumSave,
+    PLAYSPACE_turnBindLeft,
+    PLAYSPACE_turnBindRight,
+    PLAYSPACE_turnBounds,
+    PLAYSPACE_moveShortcutLeft,
+    PLAYSPACE_moveShortcutRight,
+    PLAYSPACE_dragBounds,
+    PLAYSPACE_allowExternalEdits,
+    PLAYSPACE_oldStyleMotion,
+    PLAYSPACE_universeCenteredRotation,
+    PLAYSPACE_enableSeatedMotion,
+
+    APPLICATION_disableVersionCheck,
+    APPLICATION_previousShutdownSafe,
+
+    VIDEO_brightnessEnabled,
+    VIDEO_isOverlayMethodActive,
+    VIDEO_colorOverlayEnabled,
+
+    CHAPERONE_disableChaperone,
+    // LAST_ENUMERATOR must always be set to the last value
+    LAST_ENUMERATOR = CHAPERONE_disableChaperone,
+};
+
+enum class DoubleSetting
+{
+    UTILITY_desktopWidth,
+
+    VIDEO_brightnessOpacityValue,
+    VIDEO_brightnessValue,
+    VIDEO_colorOverlayOpacity,
+    VIDEO_colorRed,
+    VIDEO_colorGreen,
+    VIDEO_colorBlue,
+    VIDEO_colorRedNew,
+    VIDEO_colorGreenNew,
+    VIDEO_colorBlueNew,
+
+    CHAPERONE_switchToBeginnerDistance,
+    CHAPERONE_hapticFeedbackDistance,
+    CHAPERONE_alarmSoundDistance,
+    CHAPERONE_showDashboardDistance,
+    CHAPERONE_fadeDistanceRemembered,
+    // LAST_ENUMERATOR must always be set to the last value
+    LAST_ENUMERATOR = CHAPERONE_fadeDistanceRemembered,
+};
+
+enum class StringSetting
+{
+    KEYBOARDSHORTCUT_keyboardOne,
+    KEYBOARDSHORTCUT_keyboardTwo,
+    KEYBOARDSHORTCUT_keyboardThree,
+    // LAST_ENUMERATOR must always be set to the last value
+    LAST_ENUMERATOR = KEYBOARDSHORTCUT_keyboardThree,
+};
+
+enum class IntSetting
+{
+    UTILITY_alarmHour,
+    UTILITY_alarmMinute,
+    // LAST_ENUMERATOR must always be set to the last value
+    LAST_ENUMERATOR = UTILITY_alarmMinute,
+};
+
+std::string initializeAndGetSettingsPath();
+
+void saveChangedSettings();
+
+void saveAllSettings();
+
+[[nodiscard]] bool getSetting( const BoolSetting setting );
+void setSetting( const BoolSetting setting, const bool value );
+
+[[nodiscard]] double getSetting( const DoubleSetting setting );
+void setSetting( const DoubleSetting setting, const double value );
+
+[[nodiscard]] int getSetting( const IntSetting setting );
+void setSetting( const IntSetting setting, const int value );
+
+[[nodiscard]] std::string getSetting( const StringSetting setting );
+void setSetting( const StringSetting setting, const std::string value );
+
+} // namespace settings