build(deps): bump @volar/language-server in /src/static/app

Bumps [@volar/language-server](https://github.com/volarjs/volar.js/tree/HEAD/packages/language-server) from 2.4.27 to 2.4.28.
- [Release notes](https://github.com/volarjs/volar.js/releases)
- [Changelog](https://github.com/volarjs/volar.js/blob/master/CHANGELOG.md)
- [Commits](https://github.com/volarjs/volar.js/commits/v2.4.28/packages/language-server)

---
updated-dependencies:
- dependency-name: "@volar/language-server"
  dependency-version: 2.4.28
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

src/static/app/package.json

@@ -12,7 +12,7 @@
     "preview": "vite preview"
   },
   "dependencies": {
-    "@volar/language-server": "2.4.27",
+    "@volar/language-server": "2.4.28",
     "@vue/language-server": "3.2.4",
     "@vuepic/vue-datepicker": "^12.1.0",
     "@vueuse/core": "^14.0.0",