feat(container.scss): add container styles for fixed position and scrolling behavior

feat(container.ts): create container module to handle scrollable behavior and add/remove disableScroll class

fix(customCursor.ts): update append target for cursor element to use container instead of main

fix(stage.ts): update append target for stage element to use container instead of main

fix(stageNav.ts): update append target for navOverlay element to use container instead of main

feat(main.ts): initialize container module and conditionally initialize stage and stageNav modules based on device type

fix(nav.ts): update references to state module functions to use state.get() instead of getState()

assets/ts/desktop/customCursor.ts

@@ -1,4 +1,5 @@
 import { active } from './stage'
+import { container } from '../container'
 
 /**
  * variables
@@ -32,7 +33,7 @@ export function initCustomCursor(): void {
   // append cursor inner to cursor
   cursor.append(cursorInner)
   // append cursor to main
-  document.getElementById('main')!.append(cursor)
+  container.append(cursor)
   // bind mousemove event to window
   window.addEventListener('mousemove', onMouse)
   // add active callback