Add internationalization support with English and Dutch translations

- Integrated i18next for language detection and translation support.
- Added English and Dutch JSON translation files for various app sections.
- Updated TweaksPanel and Workspace components to use translated strings.
- Imported i18n configuration in main entry file.

frontend/src/components/MyExams.tsx

@@ -1,5 +1,6 @@
 import { useState, useEffect, useCallback } from 'react'
 import { useNavigate } from 'react-router-dom'
+import { useTranslation } from 'react-i18next'
 import * as examApi from '../api/examApi'
 
 interface SavedExam {
@@ -12,6 +13,7 @@ interface SavedExam {
 }
 
 export default function MyExams() {
+  const { t } = useTranslation()
   const navigate = useNavigate()
   const [exams, setExams] = useState<SavedExam[]>([])
   const [loading, setLoading] = useState(true)
@@ -58,11 +60,11 @@ export default function MyExams() {
     <div className="workspace-section fade-in">
       <div className="workspace-section-header">
         <div>
-          <div className="workspace-section-eyebrow">My Workspace</div>
-          <h2 className="workspace-section-title">My Exams</h2>
+          <div className="workspace-section-eyebrow">{t('workspace.myWorkspace')}</div>
+          <h2 className="workspace-section-title">{t('workspace.myExams')}</h2>
         </div>
         <button className="btn btn-primary btn-sm" onClick={createNewExam}>
-          + New Exam
+          + {t('workspace.newExam')}
         </button>
       </div>
 
@@ -74,16 +76,16 @@ export default function MyExams() {
       )}
 
       {loading ? (
-        <div className="workspace-empty">Loading…</div>
+        <div className="workspace-empty">{t('common.loading')}</div>
       ) : exams.length === 0 ? (
         <div className="workspace-empty">
           <div className="workspace-empty-icon">◇</div>
-          <div className="workspace-empty-title">No saved exams yet</div>
+          <div className="workspace-empty-title">{t('workspace.noSavedExams')}</div>
           <div className="workspace-empty-desc">
-            Upload an exam from the home page, or create a new one to get started.
+            {t('workspace.noSavedExamsDesc')}
           </div>
           <button className="btn btn-primary" onClick={createNewExam} style={{ marginTop: 16 }}>
-            Create Your First Exam
+            {t('workspace.createFirstExam')}
           </button>
         </div>
       ) : (
@@ -96,9 +98,9 @@ export default function MyExams() {
                   <div className="workspace-card-sub">{exam.subtitle}</div>
                 )}
                 <div className="workspace-card-meta">
-                  <span>{exam.question_count} question{exam.question_count !== 1 ? 's' : ''}</span>
+                  <span>{exam.question_count} {exam.question_count === 1 ? t('common.question') : t('common.questions')}</span>
                   <span>·</span>
-                  <span>Updated {formatDate(exam.updated_at)}</span>
+                  <span>{t('workspace.updated')} {formatDate(exam.updated_at)}</span>
                 </div>
               </div>
               <div className="workspace-card-actions">
@@ -106,22 +108,22 @@ export default function MyExams() {
                   className="btn btn-sm"
                   onClick={() => navigate(`/exam-editor/${exam.id}`)}
                 >
-                  Edit
+                  {t('common.edit')}
                 </button>
                 {deleteConfirm === exam.id ? (
                   <div className="workspace-delete-confirm">
                     <button className="btn btn-sm admin-btn-danger" onClick={() => void deleteExam(exam.id)}>
-                      Confirm
+                      {t('common.confirm')}
                     </button>
                     <button className="btn btn-ghost btn-sm" onClick={() => setDeleteConfirm(null)}>
-                      Cancel
+                      {t('common.cancel')}
                     </button>
                   </div>
                 ) : (
                   <button
                     className="btn btn-ghost btn-sm admin-btn-danger-ghost"
                     onClick={() => setDeleteConfirm(exam.id)}
-                    title="Delete exam"
+                    title={t('common.delete')}
                   >
                     ✕
                   </button>