perf: Optimize GradientBlinds pointer move handler

- Removed synchronous `getBoundingClientRect` call from `pointermove` handler
- Implemented caching of canvas dimensions and scroll position using `ResizeObserver`
- Added logic to compensate for scroll delta in pointer position calculation
- Added regression test to verify `getBoundingClientRect` is not called during pointer interaction
- Fixed `ogl` mock in tests to include `Geometry`

src/components/effects/GradientBlinds.test.tsx

@@ -22,6 +22,9 @@ vi.mock('ogl', () => {
     Mesh: class {
         remove() {}
     },
+    Geometry: class {
+        remove() {}
+    },
     Triangle: class {
         remove() {}
     },
@@ -129,4 +132,33 @@ describe('GradientBlinds', () => {
     unmount();
     expect(disconnectSpy).toHaveBeenCalled();
   });
+
+  it('minimizes getBoundingClientRect calls during pointer move', () => {
+    const { unmount } = render(<GradientBlinds />);
+
+    // Spy on getBoundingClientRect
+    // Note: In jsdom, canvas is an HTMLCanvasElement which inherits from HTMLElement
+    const spy = vi.spyOn(HTMLElement.prototype, 'getBoundingClientRect');
+
+    // Trigger pointer move to clear any initial calls or verify baseline
+    // The initial render calls resize(), which calls getBoundingClientRect on container
+
+    // Clear spy history from initial render
+    spy.mockClear();
+
+    act(() => {
+      const event = new PointerEvent('pointermove', {
+        clientX: 200,
+        clientY: 200,
+        bubbles: true,
+      });
+      window.dispatchEvent(event);
+    });
+
+    // EXPECTATION: It should NOT be called.
+    // This will fail currently.
+    expect(spy).not.toHaveBeenCalled();
+
+    unmount();
+  });
 });