feat: complete i18n coverage — all dynamic content translated

All remaining French strings converted to t() calls:
- ui.js: create/delete file/dir modals, rename/copy/bookmark toasts
- palette.js: confirm dialogs, error toasts
- search.js: result summary text with interpolation
- config.js: about/diagnostics section labels
- auth.js: admin panel title
- viewer.js: forge popout labels
- dashboard.js: shared widget buttons, date locale-aware

57 new locale keys for dynamic content (modals, toasts, admin, about)
Total: 597 keys per language

All 26 modules validated — 163 exports, 0 errors

frontend/js/dashboard.js

@@ -4,6 +4,7 @@ import { state } from './state.js';
 import { escapeHtml, safeCreateIcons, getFileIcon } from './utils.js';
 import { icon, openFile } from './viewer.js';
 import { TabManager, showToast } from './ui.js';
+import { t, getLocale } from './i18n.js';
 
 // ---------------------------------------------------------------------------
 // Recent files
@@ -67,12 +68,12 @@ const DashboardSharedWidget = {
             <span class="shared-card-vault">${escapeHtml(s.vault)}</span>
           </div>
           <div class="shared-card-meta">
-            <span>${s.access_count || 0} vue(s)</span>
-            ${s.expires_at ? `<span>Expire le ${new Date(s.expires_at).toLocaleDateString("fr-FR")}</span>` : ""}
+            <span>${s.access_count || 0} ${t('dashboard.views', {count: s.access_count || 0})}</span>
+            ${s.expires_at ? `<span>${t('dashboard.expires', {date: new Date(s.expires_at).toLocaleDateString(getLocale() === 'fr' ? 'fr-FR' : 'en-US')})}</span>` : ""}
           </div>
           <div class="shared-card-actions">
-            <button class="shared-copy-btn" data-url="${window.location.origin}/s/${s.token}">📋 Copier</button>
-            <button class="shared-open-btn">📂 Ouvrir</button>
+            <button class="shared-copy-btn" data-url="${window.location.origin}/s/${s.token}">${t('dashboard.copy_btn')}</button>
+            <button class="shared-open-btn">${t('dashboard.open_btn')}</button>
             <button class="shared-revoke-btn" data-id="${s.id}">🗑</button>
           </div>
         </div>