🚨(frontend) @typescript-eslint/no-unused-vars as error

`@typescript-eslint/no-unused-vars` rules was only a warning but our code
contains several unused imports. To prevent that in the future we now trigger
an error for this rule to prevent to merge code with unused imports.

Author: jbpenrath

src/frontend/eslint.config.mjs

@@ -18,6 +18,7 @@ const eslintConfig = [
     rules: {
       "react-hooks/exhaustive-deps": "off",
       "no-console": ["error", { allow: ["error", "warn"] }],
+      "@typescript-eslint/no-unused-vars": "error",
     },
   },
 ];

src/frontend/src/features/layouts/components/thread-panel/components/thread-item/index.tsx

@@ -1,7 +1,7 @@
 import { useTranslation } from "react-i18next"
 import Link from "next/link"
 import { useParams, useSearchParams } from "next/navigation"
-import { useEffect, useRef, useState } from "react"
+import { useRef, useState } from "react"
 import { createPortal } from "react-dom"
 import clsx from "clsx"
 import { DateHelper } from "@/features/utils/date-helper"

src/frontend/src/features/layouts/components/thread-view/components/thread-message/message-body.tsx

@@ -7,7 +7,6 @@ import { UnquoteMessage } from '@/features/utils/unquote-message';
 import { useTranslation } from "react-i18next";
 import { tokens } from '@/styles/cunningham-tokens'
 import { useTheme } from "@/features/providers/theme";
-import { C } from "vitest/dist/chunks/reporters.d.BFLkQcL6.js";
 
 type MessageBodyProps = {
     rawHtmlBody?: string;