feat: Translate frontend/src/i18n/en.json in fa

54% of minimum 50% translated source file: 'frontend/src/i18n/en.json'
on 'fa'.

Sync of partially translated files: 
untranslated content is included with an empty translation 
or source language content depending on file format

frontend/src/i18n/fa.json

@@ -146,7 +146,7 @@
   "search": {
     "images": "تصاویر",
     "music": "موسیقی",
-    "pdf": "PDF",
+    "pdf": "پی دی اف",
     "pressToSearch": "Press enter to search...",
     "search": "Search...",
     "typeToSearch": "Type to search...",