npm-dep: bump tailwindcss from 4.2.0 to 4.2.1 in /frontend

Bumps [tailwindcss](https://github.com/tailwindlabs/tailwindcss/tree/HEAD/packages/tailwindcss) from 4.2.0 to 4.2.1.
- [Release notes](https://github.com/tailwindlabs/tailwindcss/releases)
- [Changelog](https://github.com/tailwindlabs/tailwindcss/blob/main/CHANGELOG.md)
- [Commits](https://github.com/tailwindlabs/tailwindcss/commits/v4.2.1/packages/tailwindcss)

---
updated-dependencies:
- dependency-name: tailwindcss
  dependency-version: 4.2.1
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

frontend/package.json

@@ -33,7 +33,7 @@
 		"prettier-plugin-tailwindcss": "^0.7.2",
 		"svelte": "^5.53.3",
 		"svelte-check": "^4.4.3",
-		"tailwindcss": "^4.2.0",
+		"tailwindcss": "^4.2.1",
 		"tslib": "^2.8.1",
 		"typescript": "^5.9.3",
 		"typescript-eslint": "^8.56.1",

frontend/pnpm-lock.yaml

@@ -91,8 +91,8 @@ importers:
         specifier: ^4.4.3
         version: 4.4.3(picomatch@4.0.3)(svelte@5.53.3)(typescript@5.9.3)
       tailwindcss:
-        specifier: ^4.2.0
-        version: 4.2.0
+        specifier: ^4.2.1
+        version: 4.2.1
       tslib:
         specifier: ^2.8.1
         version: 2.8.1