crypto: reduce allocations in WebIDL dictionary converter

Replace SafeArrayIterator with index-based loop in the inner function
returned by createDictionaryConverter, avoiding iterator object creation
on every dictionary conversion.

Replace object spread (`{ ...opts, context }`) with explicit property
assignment when passing opts to member converters. This avoids
allocating a full spread copy per dictionary member.

Signed-off-by: Filip Skokan <panva.ip@gmail.com>

Author: panva

lib/internal/crypto/webidl.js

@@ -273,7 +273,8 @@ function createDictionaryConverter(name, dictionaries) {
       return idlDict;
     }
 
-    for (const member of new SafeArrayIterator(allMembers)) {
+    for (let i = 0; i < allMembers.length; i++) {
+      const member = allMembers[i];
       const key = member.key;
 
       let esMemberValue;
@@ -289,15 +290,15 @@ function createDictionaryConverter(name, dictionaries) {
         }`;
         const idlMemberValue = member.converter(esMemberValue, {
           __proto__: null,
-          ...opts,
+          prefix: opts.prefix,
           context,
         });
         member.validator?.(idlMemberValue, esDict);
         setOwnProperty(idlDict, key, idlMemberValue);
       } else if (member.required) {
         throw makeException(
           `can not be converted to '${name}' because '${key}' is required in '${name}'.`,
-          { __proto__: null, ...opts, code: 'ERR_MISSING_OPTION' });
+          { __proto__: null, prefix: opts.prefix, context: opts.context, code: 'ERR_MISSING_OPTION' });
       }
     }