fix(settings): reset drag state before restoring default bottom bar

Tapping Restore Default mid-drag would replace `items` with the default
list while `draggedItemIndex` still pointed into the old list. If the
old index exceeded the new list's lastIndex, the next pointer event
indexed `items` out of bounds. Clear drag state before save().

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/settings/BottomBarSettingsScreen.kt

@@ -147,7 +147,11 @@ fun BottomBarSettingsContent(accountViewModel: AccountViewModel) {
             horizontalArrangement = Arrangement.End,
         ) {
             TextButton(
-                onClick = { save(initialRows(DefaultBottomBarItems)) },
+                onClick = {
+                    draggedItemIndex = -1
+                    dragOffset = 0f
+                    save(initialRows(DefaultBottomBarItems))
+                },
             ) {
                 Text(stringRes(R.string.bottom_bar_settings_restore_default))
             }