Resolve DNS records in Node PHP runtimes

[chubes4]

What

Replace the hardcoded DNS polyfill results with a Node resolver bridge for dns_check_record() / checkdnsrr(), dns_get_record(), and dns_get_mx() / getmxrr().

Supported records: A, AAAA, CAA, CNAME, MX, NAPTR, NS, PTR, SOA, SRV, and TXT. Browser runtimes retain the existing unsupported false/empty behavior.

The bridge supports both Asyncify and JSPI, preserves PHP 5/7+ Zend ownership conventions, and returns PHP-compatible record and by-reference MX array shapes.

Closes #4171.

Verification

• npx nx lint php-wasm-node
• npx tsc --noEmit -p packages/php-wasm/node/tsconfig.lib.json
• npx vitest run src/lib/wasm-user-space.spec.ts --config vite.config.ts
• PHP 8.4 Node Asyncify rebuild and A/MX integration test
• PHP 8.4 Node JSPI rebuild and A/MX integration test
• git diff --check

The focused runtime tests pass for rebuilt PHP 8.4 in both modes. Other checked-in PHP versions still carry the old binary until CI rebuilds them.

AI assistance

OpenCode with openai/gpt-5.6-sol was used to inspect the PHP-WASM/Node bridge, draft the C and TypeScript implementation, diagnose build-order, Asyncify-stack, syscall-binding, and Zend by-reference issues, and add tests. Chris Huber reviewed the source and runtime evidence and remains responsible for the change.

AI assistance: OpenAI gpt-5.6-sol via OpenCode was used to review and implement the follow-up fixes and tests.