Chore: Upgrade Vitest to v4 (#7797)

## Summary

https://vitest.dev/guide/migration.html#vitest-4

## Changes

- **What**: Update Vitest and some associated dependencies
- **What**: Fix issue with our existing mocks and mock types

## Review Focus

Double check the test updates. I tried to keep the changes minimal.

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-7797-Chore-Upgrade-Vitest-to-v4-2d96d73d3650810cbe3ac42d7bd6585a)
by [Unito](https://www.unito.io)

---------

Co-authored-by: GitHub Action <action@github.com>

tests-ui/tests/composables/useLoad3dDrag.test.ts

@@ -35,7 +35,7 @@ function createMockDragEvent(
 
 describe('useLoad3dDrag', () => {
   let mockToastStore: any
-  let mockOnModelDrop: ReturnType<typeof vi.fn>
+  let mockOnModelDrop: (file: File) => void | Promise<void>
 
   beforeEach(() => {
     vi.clearAllMocks()
@@ -199,7 +199,7 @@ describe('useLoad3dDrag', () => {
       const extensions = ['.gltf', '.glb', '.obj', '.fbx', '.stl']
 
       for (const ext of extensions) {
-        mockOnModelDrop.mockClear()
+        vi.mocked(mockOnModelDrop).mockClear()
 
         const modelFile = new File([], `model${ext}`)
         const event = createMockDragEvent('drop', {