fix(sidebar): prevent text selection when dragging project/workspace rows

The drag handle was attached only to the left sub-view of each row, so
grabbing the right half initiated no drag, and pointerdown on the branch
or project title raced the browser's text-selection start before
dnd-kit's activation threshold — often producing a text selection
instead of a drag.

Move dragHandleProps to the outer row wrapper, add userSelect: none to
the row styles, and tighten PointerSensor activation distance.

packages/app/src/components/draggable-list.web.tsx

@@ -142,7 +142,7 @@ export function DraggableList<T>({
   const sensors = useSensors(
     useSensor(PointerSensor, {
       activationConstraint: {
-        distance: 8,
+        distance: 6,
       },
     }),
     useSensor(KeyboardSensor, {