feat(input): add viewport wheel zoom and panning

input/index.ts

@@ -6,4 +6,5 @@ export {
 export type { CommandKeybind, GlobalKeybindConsumer, Keybind, KeybindEvent, KeybindMap } from "./keyboard";
 export { handleKeybind, keybindFromEvent } from "./keyboard";
 export type { GlobalPointerConsumer, GlobalWheelConsumer, PointerInputEvent, WheelInputEvent } from "./pointer";
-export { handleViewportWheel } from "./viewport";
+export type { ViewportPointerPanHandler } from "./viewport";
+export { createViewportPointerPanHandler, handleViewportWheel } from "./viewport";