Fixes: #64780

Description

This pull request aligns URLPatternInit dictionary conversion with the WHATWG / WebIDL specifications:

1. Member access order: Read URLPatternInit dictionary members in lexicographical order (baseURL, hash, hostname, password, pathname, port, protocol, search, username), ensuring getters and proxy traps observe the access sequence required by WebIDL.
2. Absent members: Use sparse DictionaryTemplate values (tmpl->NewInstance(context, values)) so that absent dictionary members in URLPatternResult.inputs are omitted rather than exposed as own enumerable properties with undefined values.

Verification

• Added regression tests in test/parallel/test-urlpattern.js verifying lexicographical access order on Proxy getters and omission of absent members in exec().inputs.
• Verified formatting and linting via python tools/cpplint.py src/node_url_pattern.cc.