fix(people): extend exact ASGI scalar authority to confirmed-hire ingress

[seonghobae]

Finding

Fresh audit of canonical People owner #55 after #322 shows the confirmed-hire HTTP boundary still has the predecessor scalar semantics even though it consumes the now-hardened shared Authorization-header parser.

At current #55 head 677aaace49e88f20504252cda61cbeb812e0f6c0, HireAcceptanceAsgiApp still:

• compares scope["type"] and scope["method"] before proving exact built-in str;
• accepts path through isinstance(path, str) before len/tokenization;
• accepts query_string through isinstance(raw_query, bytes) before len/decode;
• accepts authenticator output through isinstance(principal, AuthenticatedPrincipal) rather than the exact principal boundary already used by canonical People GET.

The shared _authorization_header is fixed by #322, but these hire-local ingress checks can still admit behavior-bearing Python subtypes before or across authentication. Existing oversized-input tests prove bounds but do not prove inert exact scalar authority.

Required repair

Use a dedicated test-first hire scalar-integrity contract with trapping str/bytes subtypes, preserving existing ValueError/405/404/400/500 semantics and proving zero mutation calls on rejection. Then apply the minimum hire-local exact-type gates. Do not copy sibling Employment/Position implementations; keep #55 as the canonical writer.

Also audit post-authentication idempotency/content-type header parsing separately rather than assuming the shared Authorization-header repair covers those fields.

Keep open until the exact repaired #55 head has normal protected acceptance and integration. No force-push, destructive rebase, self/model approval, no-op retrigger, predecessor-evidence transfer, or gate weakening.

[seonghobae]

#323 repair is now on canonical People owner PR #55.

• test-first source commit: 6db4569cedd54b73da6463fb60513edeedc52757
• causal repair: c4d04b7170cddd0e8fc7d2ed2406ca5037cbbfb3
• confirmed-hire now requires exact built-in scalar authority for ASGI scope type, method, path, query bytes, authenticator principal, and post-authentication Idempotency-Key / Content-Type values before comparison, length, tokenization, decode, split, or protected mutation execution.
• regressions include an authenticator that mutates scope["headers"] after authentication, proving the post-auth parser does not trust the previously checked header objects.

The test-only head's hosted runs were superseded and cancelled, so they are not claimed as hosted RED. Current repaired exact-head CodeQL 34831381372, Security 34831381384, Foundation 34831381432, and SAST 34831381441 are queued; no hosted GREEN or independent approval is claimed yet.

Employment descendants were ordinary-forward restacked without force: #149 72095d693bd2c2a27a174674aad1f0180adb0669 → #155 85449636d4564eb6352e925256f1f99a01e6250f → #156 061cba0462baf59de535f61a16fe5b2988a9027c.

Keep this finding open until the repaired #55 exact head passes protected acceptance and integrates normally.