feat(wallpaper): support configurable background color (#2671)

* feat(wallpaper): support configurable background color

* chore(translations): update settings search index

* revert(wallpaper): keep Pad naming instead of Center

quickshell/Common/SettingsData.qml

@@ -242,6 +242,24 @@ Singleton {
     property string wallpaperFillMode: "Fill"
     property bool blurredWallpaperLayer: false
     property bool blurWallpaperOnOverview: false
+    property string wallpaperBackgroundColorMode: "black"
+    property string wallpaperBackgroundCustomColor: "#000000"
+    readonly property color effectiveWallpaperBackgroundColor: {
+        switch (wallpaperBackgroundColorMode) {
+        case "black":
+            return "#000000";
+        case "white":
+            return "#ffffff";
+        case "primary":
+            return Theme.primary;
+        case "surface":
+            return Theme.surfaceContainer;
+        case "custom":
+            return wallpaperBackgroundCustomColor;
+        default:
+            return "#000000";
+        }
+    }
 
     property bool frameEnabled: false
     onFrameEnabledChanged: saveSettings()

quickshell/Common/settings/SettingsSpec.js

@@ -74,6 +74,8 @@ var SPEC = {
     wallpaperFillMode: { def: "Fill" },
     blurredWallpaperLayer: { def: false },
     blurWallpaperOnOverview: { def: false },
+    wallpaperBackgroundColorMode: { def: "black" },
+    wallpaperBackgroundCustomColor: { def: "#000000" },
 
     showLauncherButton: { def: true },
     showWorkspaceSwitcher: { def: true },