launcher: implement memory for selected tab

fixes #1806

quickshell/Common/SessionData.qml

@@ -126,6 +126,10 @@ Singleton {
     property var hiddenOutputDeviceNames: []
     property var hiddenInputDeviceNames: []
 
+    property string launcherLastMode: "all"
+    property string appDrawerLastMode: "apps"
+    property string niriOverviewLastMode: "apps"
+
     Component.onCompleted: {
         if (!isGreeterMode) {
             loadSettings();
@@ -1100,6 +1104,21 @@ Singleton {
         saveSettings();
     }
 
+    function setLauncherLastMode(mode) {
+        launcherLastMode = mode;
+        saveSettings();
+    }
+
+    function setAppDrawerLastMode(mode) {
+        appDrawerLastMode = mode;
+        saveSettings();
+    }
+
+    function setNiriOverviewLastMode(mode) {
+        niriOverviewLastMode = mode;
+        saveSettings();
+    }
+
     function syncWallpaperForCurrentMode() {
         if (!perModeWallpaper)
             return;

quickshell/Common/settings/SessionSpec.js

@@ -77,7 +77,11 @@ var SPEC = {
 
     deviceMaxVolumes: { def: {} },
     hiddenOutputDeviceNames: { def: [] },
-    hiddenInputDeviceNames: { def: [] }
+    hiddenInputDeviceNames: { def: [] },
+
+    launcherLastMode: { def: "all" },
+    appDrawerLastMode: { def: "apps" },
+    niriOverviewLastMode: { def: "apps" }
 };
 
 function getValidKeys() {