feat(settings): add screensaver toggle in Language tab (default off)

Toggle appears in the Language settings tab, below the language selector.
Default: disabled. When disabled, initInactivityWatcher() exits early so
the screensaver never activates. i18n added for it/en/de.

assets/js/app.js

@@ -1101,6 +1101,9 @@ function translatePage() {
 // Populate the language selector dropdown
 function _populateLanguageSelector() {
     const sel = document.getElementById('setting-language');
+    // Screensaver toggle
+    const ssEl = document.getElementById('setting-screensaver-enabled');
+    if (ssEl) ssEl.checked = s.screensaver_enabled === true;
     if (!sel) return;
     sel.innerHTML = '';
     for (const [code, name] of Object.entries(_SUPPORTED_LANGS)) {
@@ -2124,6 +2127,9 @@ async function saveSettings() {
     s.dietary = document.getElementById('setting-dietary').value.trim();
     // Camera
     s.camera_facing = document.getElementById('setting-camera-facing').value;
+    // Screensaver
+    const ssEl = document.getElementById('setting-screensaver-enabled');
+    if (ssEl) s.screensaver_enabled = ssEl.checked;
     // Meal plan enabled toggle
     const mpEnabledEl = document.getElementById('setting-meal-plan-enabled');
     if (mpEnabledEl) s.meal_plan_enabled = mpEnabledEl.checked;
@@ -11691,6 +11697,8 @@ function initScreensaverShortcuts() {
 }
 
 function initInactivityWatcher() {
+    const s = getSettings();
+    if (!s.screensaver_enabled) return; // disabled by default
     const events = ['pointerdown', 'pointermove', 'keydown', 'scroll', 'touchstart'];
     events.forEach(evt => {
         document.addEventListener(evt, () => {

index.html

@@ -1088,6 +1088,17 @@
                         <p class="settings-hint mt-2" data-i18n="settings.language.restart_notice">La pagina verrà ricaricata per applicare la nuova lingua.</p>
                     </div>
                 </div>
+                <div class="settings-card">
+                    <h4>🌑 Salvaschermo</h4>
+                    <p class="settings-hint">Mostra un orologio con fatti utili dopo 5 minuti di inattività. Di default è disattivato.</p>
+                    <div class="form-group">
+                        <label class="toggle-label">
+                            <input type="checkbox" id="setting-screensaver-enabled" class="toggle-input">
+                            <span class="toggle-slider"></span>
+                            <span class="toggle-text" data-i18n="settings.screensaver.label">Attiva salvaschermo</span>
+                        </label>
+                    </div>
+                </div>
             </div>
         </div>
 

translations/de.json

@@ -595,6 +595,9 @@
             "label": "🌐 Sprache",
             "restart_notice": "Die Seite wird neu geladen, um die neue Sprache anzuwenden."
         },
+        "screensaver": {
+            "label": "Bildschirmschoner aktivieren"
+        },
         "scale": {
             "title": "⚖️ Smart-Waage",
             "hint": "Verbinde eine Bluetooth-Waage über das Android-Gateway, um das Gewicht automatisch auszulesen.",

translations/en.json

@@ -594,6 +594,9 @@
             "label": "🌐 Language",
             "restart_notice": "The page will reload to apply the new language."
         },
+        "screensaver": {
+            "label": "Enable screensaver"
+        },
         "scale": {
             "title": "⚖️ Smart Scale",
             "hint": "Connect a Bluetooth scale via the Android gateway to automatically read weight.",

translations/it.json

@@ -594,6 +594,9 @@
             "label": "🌐 Lingua",
             "restart_notice": "La pagina verrà ricaricata per applicare la nuova lingua."
         },
+        "screensaver": {
+            "label": "Attiva salvaschermo"
+        },
         "scale": {
             "title": "⚖️ Bilancia Smart",
             "hint": "Collega una bilancia Bluetooth tramite il gateway Android per leggere il peso automaticamente.",