fix: discard pending sidebar width on collapse

frontend/src/renderer/components/Sidebar.test.tsx

@@ -511,4 +511,37 @@ describe("Sidebar", () => {
 		expect(document.documentElement.style.getPropertyValue("--ao-sidebar-w")).toBe("280px");
 		expect(window.localStorage.getItem("ao-sidebar-w")).toBe("280");
 	});
+
+	it("discards a queued narrow resize frame when collapsing", async () => {
+		let queuedFrame: FrameRequestCallback | undefined;
+		const requestAnimationFrameSpy = vi.spyOn(window, "requestAnimationFrame").mockImplementation((callback) => {
+			queuedFrame = callback;
+			return 1;
+		});
+		const cancelAnimationFrameSpy = vi.spyOn(window, "cancelAnimationFrame").mockImplementation(() => undefined);
+
+		try {
+			renderSidebar();
+
+			const resizeHandle = document.querySelector(".resize-handle--right");
+			if (!(resizeHandle instanceof HTMLElement)) throw new Error("Resize handle not found");
+
+			fireEvent.pointerDown(resizeHandle, { clientX: 240 });
+			fireEvent.pointerMove(window, { clientX: 205 });
+			fireEvent.pointerMove(window, { clientX: 120 });
+
+			await waitFor(() => {
+				expect(document.querySelector('[data-slot="sidebar"][data-state="collapsed"]')).toBeInTheDocument();
+			});
+			expect(cancelAnimationFrameSpy).toHaveBeenCalledWith(1);
+			expect(window.localStorage.getItem("ao-sidebar-w")).toBe("240");
+			expect(document.documentElement.style.getPropertyValue("--ao-sidebar-w")).toBe("240px");
+
+			queuedFrame?.(performance.now());
+			expect(document.documentElement.style.getPropertyValue("--ao-sidebar-w")).toBe("240px");
+		} finally {
+			requestAnimationFrameSpy.mockRestore();
+			cancelAnimationFrameSpy.mockRestore();
+		}
+	});
 });

frontend/src/renderer/hooks/useResizable.ts

@@ -79,6 +79,14 @@ export function useResizable({
 		if (pending !== null) apply(pending);
 	}, [apply]);
 
+	const discardPending = useCallback(() => {
+		if (frameRef.current !== null) {
+			window.cancelAnimationFrame(frameRef.current);
+			frameRef.current = null;
+		}
+		pendingWidthRef.current = null;
+	}, []);
+
 	// Restore persisted width on mount.
 	useEffect(() => {
 		const saved = Number(window.localStorage.getItem(storageKey));
@@ -109,8 +117,10 @@ export function useResizable({
 				const nextWidth = startWidth + sign * (e.clientX - startX);
 				if (collapseBelow !== undefined && onCollapse && nextWidth <= collapseBelow) {
 					collapsed = true;
-					flushPending();
-					window.localStorage.setItem(storageKey, String(Math.min(max, Math.max(min, startWidth))));
+					const preservedWidth = Math.min(max, Math.max(min, startWidth));
+					discardPending();
+					apply(preservedWidth);
+					window.localStorage.setItem(storageKey, String(preservedWidth));
 					onUp();
 					onCollapse();
 					return;
@@ -120,7 +130,7 @@ export function useResizable({
 			window.addEventListener("pointermove", onMove);
 			window.addEventListener("pointerup", onUp);
 		},
-		[applyOnFrame, collapseBelow, edge, flushPending, max, min, onCollapse, storageKey],
+		[apply, applyOnFrame, collapseBelow, discardPending, edge, flushPending, max, min, onCollapse, storageKey],
 	);
 
 	const onCollapsedPointerDown = useCallback(