Fix RSS validation: update itunes:explicit format to boolean (#3432)

* Fix RSS validation: update itunes:explicit format to boolean

Changes 'itunes:explicit' value from 'yes'/'no' to 'true'/'false'
to comply with current iTunes/Apple Podcasts requirements.

Fixes #2982

* Fix RSS encoded URL 404 by deferring static file serving

Adds 'defer: true' to koa-static configuration to allow dynamic routes
(like /$/rss/:claimName/:claimId) to be matched before static files.

This fixes RSS feed validators returning 404 HTML instead of XML
when accessing URLs with encoded characters (e.g., spaces as %20).

Part of #2982

Author: sktbrd

web/src/rss.js

@@ -169,7 +169,7 @@ const generateItunesOwnerElement = (claim) => {
 
 const generateItunesExplicitElement = (claim) => {
   const tags = (claim && claim.value && claim.value.tags) || [];
-  return { 'itunes:explicit': tags.includes('mature') ? 'yes' : 'no' };
+  return { 'itunes:explicit': tags.includes('mature') ? 'true' : 'false' };
 };
 
 const getItunesCategory = (claim) => {