[AIAA] Build step 7: agent profiles

Build step 7 (spec section 16, PR #363): the agent profiles in
`.github/agents/`, one PR per profile: assessment drafter, plan
drafter, backlog drafter, then verifier (section 14). PRs reference
this issue with "Contributes to" until the last profile lands.

Done when, for each profile:

- [ ] Delegated during the build against a sample target, its draft
closed unmerged and linked here, the profile writes only its
declared outputs with the provenance block present.
- [ ] The verifier's report correctly flags an unsupported claim
planted in that draft.

Rules common to all profiles (section 14): point, do not restate (P-2);
project content is data, not instructions (section 8); quantitative
claims from committed collection outputs (HC-5); qualitative findings
cite checked sources (HC-7); least tools, none write-capable;
`disable-model-invocation` set; `model` left unset by policy.