Make every settings row reachable, and every accessibility switch honest

Claude-Session: https://claude.ai/code/session_01Ms2FbjQy31TVf3CEvQhGM8

config/dot/quickshell/modules/settings/SliderRow.qml

@@ -81,6 +81,22 @@ Item {
         return root.step < 1 ? Math.round(clamped * 100) / 100 : clamped;
     }
 
+    // One schema step, from the arrow keys, committed through the same debounce
+    // the pointer drag uses -- holding an arrow reads as a drag rather than as
+    // a burst of writes the compositor would spend the whole time rejecting.
+    function nudge(steps: int): void {
+        const raw = root.shown + steps * root.step;
+        const clamped = Math.max(root.minimum, Math.min(root.maximum, raw));
+        root.pending = root.step < 1 ? Math.round(clamped * 100) / 100 : clamped;
+        commitTimer.restart();
+    }
+
+    // What a screen reader is told the slider is sitting on. Qt 6.11's attached
+    // Accessible type carries no structured value or range, so the reading and
+    // its bounds go in the description, in the row's own display units.
+    readonly property string reading:
+        `${root.display(root.shown)}, ${root.display(root.minimum)} to ${root.display(root.maximum)}`
+
     function display(value: real): string {
         if (value === 0 && root.zeroLabel !== "")
             return root.zeroLabel;
@@ -145,6 +161,35 @@ Item {
                 root.pending = root.quantise(ratio);
                 commitTimer.restart();
             }
+
+            activeFocusOnTab: true
+
+            Accessible.role: Accessible.Slider
+            Accessible.name: root.label
+            Accessible.description: root.detail === ""
+                ? root.reading
+                : `${root.detail} — ${root.reading}`
+            Accessible.focusable: true
+            Accessible.focused: slider.activeFocus
+            Accessible.onIncreaseAction: root.nudge(1)
+            Accessible.onDecreaseAction: root.nudge(-1)
+
+            Keys.onLeftPressed: root.nudge(-1)
+            Keys.onDownPressed: root.nudge(-1)
+            Keys.onRightPressed: root.nudge(1)
+            Keys.onUpPressed: root.nudge(1)
+
+            // Drawn only while the slider holds keyboard focus: transparent
+            // fill, so at rest there is nothing here at all.
+            Rectangle {
+                anchors.fill: parent
+                anchors.margins: -2
+                radius: 9
+                color: "transparent"
+                visible: slider.activeFocus
+                border.width: 2
+                border.color: Theme.accentSecondary
+            }
         }
 
         Text {