Deliver buffered HTTP response-metadata views #106

Parent

Spec: Complete the review-driven Effect API Query 0.1.0 programme

What to build

Consumers can request decoded data plus status/header snapshots while ordinary buffered queries retain their behavior.

Acceptance criteria

• Add an explicitly separate metadata view/identity with truthful query-data and published error/service types.
• Obtain decoded data and response metadata through the ready client's supported contract, then retain only immutable plain metadata.
• Preserve existing declared decoded header wrappers and ordinary query/infinite/mutation behavior.
• Verify status/header/data values, request encoding, failures, cancellation, and no retained open response/body resources.
• Provide ordinary factory runtime tests, public API compiler fixtures, and an ETag/metadata-focused recipe without creating a new application.