chore(deps-dev): bump vitest from 3.2.4 to 4.1.5 (#1748)

* chore(deps-dev): bump vitest from 3.2.4 to 4.1.5

Bumps [vitest](https://github.com/vitest-dev/vitest/tree/HEAD/packages/vitest) from 3.2.4 to 4.1.5.
- [Release notes](https://github.com/vitest-dev/vitest/releases)
- [Commits](https://github.com/vitest-dev/vitest/commits/v4.1.5/packages/vitest)

---
updated-dependencies:
- dependency-name: vitest
  dependency-version: 4.1.5
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

* chore(deps-dev): update @vitest/coverage-v8

Bump @vitest/coverage-v8 to ^4.1.5 to match peer dependency, and move
vi.mock('node:fs') calls to the top level of test files to reflect
actual hoisting semantics required by vitest 4.x.

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Tom Keller <kellertk@amazon.com>

package.json

@@ -21,7 +21,7 @@
     "@biomejs/biome": "2.4.13",
     "@smithy/property-provider": "^4.2.14",
     "@types/node": "^25.6.0",
-    "@vitest/coverage-v8": "^3.2.4",
+    "@vitest/coverage-v8": "^4.1.5",
     "aws-sdk-client-mock": "^4.1.0",
     "esbuild": "^0.28.0",
     "generate-license-file": "^4.1.1",
@@ -30,7 +30,7 @@
     "memfs": "^4.57.2",
     "standard-version": "^9.5.0",
     "typescript": "^6.0.3",
-    "vitest": "^3.2.4"
+    "vitest": "^4.1.5"
   },
   "dependencies": {
     "@actions/core": "^2.0.2",