fix: show/hide arrow always visible and null-safe

- Show arrow (›) appears when toolbar is hidden, regardless of pos state
- Null-safe pos top/left (?. ?? 8) to prevent TS errors
- Arrow positioned fixed top-right instead of depending on balk-positie

src/app/client/client-view.tsx

@@ -295,8 +295,8 @@ export function ClientView({
 					ref={toolbarRef}
 					className="fixed z-[9999] rounded-2xl shadow-2xl px-1.5 py-1.5 select-none backdrop-blur-2xl"
 					style={{
-						top: pos.top,
-						left: pos.left,
+						top: pos?.top ?? 8,
+						left: pos?.left ?? 8,
 						transition: snapTween
 							? "top 0.18s ease-out, left 0.18s ease-out"
 							: undefined,
@@ -540,7 +540,7 @@ export function ClientView({
 				</div>
 			) : null}
 
-			{barHidden && pos ? (
+			{barHidden ? (
 				<button
 					type="button"
 					onPointerDown={(e) => {
@@ -549,8 +549,8 @@ export function ClientView({
 					}}
 					className="fixed z-[9999] h-8 rounded-xl flex items-center justify-center px-2 cursor-pointer transition-all duration-200 opacity-80 hover:opacity-100 hover:-translate-y-0.5 active:translate-y-0 active:scale-90"
 					style={{
-						top: pos.top,
-						left: pos.left,
+						top: pos?.top ?? 8,
+						left: pos?.left ?? 8,
 						border:
 							"1px solid color-mix(in srgb, var(--color-primary, #eeb425) 85%, white)",
 						background: