Selettore lingua (System/EN/IT) nelle impostazioni con QTranslator in main.cpp (pattern quill); fix 'Close book' con pop fino alla prima pagina

qml/pages/ReaderPage.qml

@@ -57,7 +57,10 @@ Page {
                 text: qsTr("Close book")
                 onClicked: {
                     page.maybeSave(true)
-                    pageStack.popTo(null)
+                    // torna alla prima pagina dello stack (MainPage):
+                    // popTo(null) non è affidabile su questa Silica
+                    while (pageStack.depth > 1)
+                        pageStack.pop()
                 }
             }
         }

qml/pages/SettingsPage.qml

@@ -7,6 +7,7 @@ Page {
     property string testResult: ""
     property bool testOk: false
     property bool testing: false
+    property string languageNotice: ""
 
     SilicaFlickable {
         anchors.fill: parent
@@ -111,6 +112,43 @@ Page {
                 visible: text.length > 0
             }
 
+            SectionHeader { text: qsTr("Language") }
+
+            ComboBox {
+                id: langBox
+                width: parent.width
+                label: qsTr("Language")
+                currentIndex: appSettings.language === "it" ? 2 : (appSettings.language === "en" ? 1 : 0)
+                menu: ContextMenu {
+                    MenuItem { text: qsTr("System (default)") }
+                    MenuItem { text: "English" }
+                    MenuItem { text: "Italiano" }
+                }
+                onCurrentIndexChanged: {
+                    var v = currentIndex === 2 ? "it" : (currentIndex === 1 ? "en" : "system")
+                    if (v !== appSettings.language) {
+                        appSettings.language = v
+                        page.languageNotice = qsTr("Language will be applied after restarting the app")
+                        langNoticeTimer.restart()
+                    }
+                }
+            }
+
+            Label {
+                x: Theme.horizontalPageMargin
+                width: parent.width - 2 * Theme.horizontalPageMargin
+                text: page.languageNotice
+                color: Theme.highlightColor
+                wrapMode: Text.Wrap
+                visible: text.length > 0
+            }
+
+            Timer {
+                id: langNoticeTimer
+                interval: 4000
+                onTriggered: page.languageNotice = ""
+            }
+
             Item { width: 1; height: Theme.paddingLarge }
         }
     }