feat: show full supported-platforms block on each downloader page

Replace the plain "looking for another platform?" text link at the
bottom of each per-platform page with the same SupportedPlatformsSection
used on the homepage, giving stronger internal linking between all
platform pages. Drop the now-unused otherPlatforms/browseAll strings.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

messages/es.json

@@ -96,9 +96,7 @@
     "heading": "Descargador de {platform}",
     "subheading": "Pega un enlace de {platform} abajo y obtén tu archivo en segundos — gratis, sin cuenta.",
     "aboutHeading": "Sobre la descarga desde {platform}",
-    "faqHeading": "FAQ del descargador de {platform}",
-    "otherPlatforms": "¿Buscas otra plataforma?",
-    "browseAll": "Explorar todos los sitios compatibles"
+    "faqHeading": "FAQ del descargador de {platform}"
   },
   "downloaderPages": {
     "youtube": {