fix(kiosk): dismiss on-screen keyboard on accept and tap-outside

The OSK opened on kiosk search/inputs but never closed: focus stayed on
the search field. Clear focus in the field's `accepted` handler and add a
full-bleed background TouchArea that clears focus on any tap outside the
input, so the on-screen keyboard dismisses.

cc

crates/qbz-ui/ui/shell/KioskShell.slint

@@ -176,6 +176,10 @@ export component KioskShell inherits Rectangle {
                     accepted(text) => {
                         SearchActions.submit(text);
                         NavState.view = ContentView.search;
+                        // Release focus so Slint sends text-input DISABLE → the OS
+                        // on-screen keyboard (squeekboard) closes. Otherwise the
+                        // search field keeps focus forever and the OSK never hides.
+                        search-field.clear-focus();
                     }
                 }
             }
@@ -193,6 +197,14 @@ export component KioskShell inherits Rectangle {
         Rectangle {
             vertical-stretch: 1;
             background: Theme.surface-card;
+            // Tap anywhere in the content area to dismiss the OS on-screen
+            // keyboard: release the search field's focus → Slint sends the
+            // text-input DISABLE → squeekboard closes. Declared FIRST so it sits
+            // BEHIND the views (which handle their own taps); it only catches
+            // empty-area taps.
+            dismiss-osk-ta := TouchArea {
+                clicked => { search-field.clear-focus(); }
+            }
             VerticalLayout {
                 vertical-stretch: 1;
                 padding-left: 8px;