[web] Convert some Features files to ES modules (part 4) GitOrigin-RevId: cf11a7584e39c4d4de08e2f924240e488a4066c4
* Rename files to mjs * Rename test files to mjs * Update CODEOWNERS * Update files to ESM * Update test files to ESM * Update RestoreManager.test.mjs * Remove unused `AdminAuthorizationHelper` mock and stub * Remove unnecessary return GitOrigin-RevId: 2b9ef126de1d8964afbc6e5641cca36712655866