Inspect changes since a previous read

Optional configuration: pass the prior contentHash as if_none_match on the same URL and the same materialization settings.

This capture used GitHub Release host v1.1.1. It returned unchanged:true and empty markdown — the second read matched the first-read hash from the same session.

• result-summary.json
• settings.json · input-metadata.json

diff_against is a separate opt-in for block-level deltas and was not used here.