fix(react): address Doctor findings (#1143)

Accessibility/semantics pass aligned with React Doctor: role-based spans/divs become real buttons, role=status becomes <output>, modals use native <dialog>, author/peer flags render as <img>, and embed/challenge iframes are sandboxed. Includes review follow-ups: correct button chrome/centering/themed dialog colors and focus rings, the missing aria-label i18n keys (all languages), the Yandex image-search URL, clearer .bso setup steps, a keyboard-accessible image-search dropdown, and removal of the post-edit ('comment edited') display (mod edits unchanged).

public/translations/fr/default.json

@@ -144,10 +144,6 @@
   "show_worksafe_boards_only": "Afficher uniquement les tableaux Worksafe",
   "show_all_content": "Afficher tout le contenu",
   "link_type": "Type de lien",
-  "comment_edited_at_timestamp": "Commentaire modifié le <1>{{timestamp}}</1>",
-  "reason_reason": "Raison: \"{{reason}}\".",
-  "click_here_to_show_original": "<1>Cliquez ici</1> pour afficher l'original.",
-  "click_here_to_hide_original": "<1>Cliquez ici</1> pour masquer l'original.",
   "loading": "Chargement",
   "posted_by": "Posté par",
   "by": "par",
@@ -393,5 +389,13 @@
   "go_to_settings_to_import_mod_account": "Allez dans les <1>paramètres</1> pour importer votre compte de modération",
   "post_form_rules_faq_prompt": "Veuillez lire le <rules>Règlement</rules> et la <faq>FAQ</faq> avant de publier.",
   "pending_mod_approval_reason": "La modération par IA a envoyé ce post dans la file de modération. Raison: \"{{reason}}\".",
-  "flag": "Drapeau"
+  "flag": "Drapeau",
+  "show_replies": "afficher les réponses",
+  "hide_replies": "masquer les réponses",
+  "unhide": "afficher",
+  "account_data": "données du compte",
+  "ban_duration_days": "durée du bannissement en jours",
+  "challenge_answer": "réponse au défi",
+  "ban": "interdire",
+  "timestamp": "horodatage"
 }