chore(deps): update dependency tailwindcss to ^4.1.15 (#6902)

This PR contains the following updates:

| Package | Change | Age | Confidence |
|---|---|---|---|
| [tailwindcss](https://tailwindcss.com)
([source](https://redirect.github.com/tailwindlabs/tailwindcss/tree/HEAD/packages/tailwindcss))
| [`^4.1.14` ->
`^4.1.15`](https://renovatebot.com/diffs/npm/tailwindcss/4.1.15/4.1.15)
|
[![age](https://developer.mend.io/api/mc/badges/age/npm/tailwindcss/4.1.15?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/tailwindcss/4.1.15/4.1.15?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

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frontend/package.json

@@ -247,7 +247,7 @@
     "storybook": "^9.1.8",
     "stylelint": "^16.23.1",
     "stylelint-config-standard": "^36.0.1",
-    "tailwindcss": "^4.1.14",
+    "tailwindcss": "^4.1.15",
     "vite": "npm:rolldown-vite@^7.1.19",
     "vite-plugin-top-level-await": "^1.6.0",
     "vite-plugin-wasm": "^3.5.0",