* Add pr-stamp-sweep review workflow
Adds a reusable workflow script that fans out one reviewer agent per
candidate PR to judge whether it can be approved as-is, then runs an
adversarial verification pass on each approval recommendation before
including it in the final list.
Reviewers read pre-fetched PR dossiers from /tmp/claude/pr-sweep/<n>.md
(metadata, body, comments, full diff) rather than calling gh directly,
and verify diff claims against the local checkout. PR numbers are
passed via args; the script fails fast if none are provided.
* Sharpen security checklist in reviewer prompts
Replace the general security-history note with explicit attack classes
both reviewer stages must check: prompt injection (untrusted content
reaching Claude's context, including via tool output), code execution
(shell commands, eval/spawn, workflow expressions), path traversal,
and credential exposure.
