CIT-0: neutral citation target

[briansrls]

Summary

CIT-0 neutral citation substrate — three-carrier model:

• CitationTarget — expected_pin + valid CitationSelector only (no embedded retrieval observation).
• CitationRetrievalObservation — dated request receipt (RepresentationRetrieved, access refused, unreachable, rate-limited, response-without-representation).
• CitationVerificationReceipt — explicit join of target + observation + reconciliation verdict.

Other landed facts:

• Symbolic source: Pin<CitedRepresentationIdentity> grounds source on ExternalSubjectRef, with access_route and byte_domain as separate identity axes.
• Canonical URI equality: extdeps.uri uri_eq compares scheme + locator; used in identity reconciliation and request binding (http vs https on the same locator are distinct).
• Honest verification outcomes: only RepresentationMatch inhabits CitationRepresentationVerified; mismatch/incomparable/missing are separate terminal arms — no absorbing success.
• Selector construction wall: CitationSelectorConstruction = Constructed | Refused; CitationSelector carries valid arms only.
• HTTP success gate: RepresentationRetrieved with non-2xx status refuses verification (HttpStatusNotSuccessful).
• Typed non-retrieval refusals: unreachable/access-refused/rate-limited/204 preserve their observation arm in refusal causes.
• citation_exact_pin: Sha256Digest admission boundary only; reconcile max conclusion is supplied-equals-supplied.

Test plan

• citation_cit0_witness_test green by execution (scheme mismatch, HTTP 404 refusal, verified-vs-mismatch split, selector construction, identity/reconcile controls).

[gunbai-bot]

Addressed review 47926 (retry_after_seconds finding).

Fix (dafadbb): CitationRateLimited.retry_after_seconds: Int? → retry_after: Second? with import std.measure { Second } — duration now rides the measured-time carrier, not a bare Int in std/.

Collateral: importing std.measure pulls extdeps.units.* into the witness closure, where homonymous extdeps_external_authority_anchor rows shadow the web-annotation symbol at eval time. Added web_annotation_authority (inlined URI, citation-facing name) in extdeps.standards.web_annotation and pointed std.citation + the witness at it. 8/8 citation_cit0_witness_test fns green by execution.

— sent from smart-cat-178

[gunbai-bot]

review 47935 — duplicate authority anchor: fixed (3294caaf47)

Verified against current code: web_annotation_authority was re-minting the same Uri block as extdeps_external_authority_anchor at lines 15–20. That is a same-file parallel representation.

Fix: data web_annotation_authority: ExternalAuthority = extdeps_external_authority_anchor — the established extdeps alias pattern (jq_authority precedent). The citation-facing export name is preserved for the std.measure homonym disambiguation; the cited fact has one editable source.

Witness: web_annotation_authority_is_cited_for_selectors now proves alias identity (web_annotation_authority.uri.locator == extdeps_external_authority_anchor.uri.locator), matching provider_lifecycle_witness_test — not a second string literal. 13/13 citation_cit0_witness_test green locally.

— sent from smart-cat-178

[gunbai-bot]

Read review 48922 against 80a5aca.

Both minor notes are intentional CIT-0 choices, not gaps:

1. Zero-length TextPositionSelector (end == start) — admitted in text_position_selector's Equal arm; W3C TextPositionSelector allows a degenerate range and we only refuse end < start (TextPositionEndBeforeStart). Happy to add an explicit sentence to text_position_selector_cross_field_note in a follow-up if the operator wants the note to carry it; not blocking merge.

2. uri_eq exact-string locator match — deliberate fail-closed CIT-0 binding (RequestLocatorMismatch on any string mismatch including trailing-slash drift). URI normalization belongs in CIT-1+ (citation_fragment_selector_conforms_to / fragment open-parameter work), not silently absorbed here.

No code change from this review.

— sent from smart-cat-178

[gunbai-bot]

Addressed review 48947 (REQUEST_CHANGES on uri_eq).

Fix (31ec542): deleted uri_eq from extdeps.uri and regen; std.citation + citation_cit0_witness_test now use substrate Uri == / != directly (cited_representation_identity_eq, verify_citation_representation locator checks). Agree with the finding — Uri is a closed record and rest.dag already dissolved the parallel rest_uri_eq predicate for the same §2/§3 reason.

CI re-running on the new head.

— sent from smart-cat-178

[gunbai-bot]

Read review 49053 (APPROVE).

Both non-blocking observations are already the intended CIT-0 posture:

1. TransportUnreachable — named fifth arm, not a silent catch-all; citation_unreachable_cause_note states unclassifiable transport failures must land on a separate arm when that layer lands (CIT-2 transport observation work).

2. web_annotation_authority — citation-facing export alias to extdeps_external_authority_anchor for the std.measure homonym disambiguation in witness closures; single editable cited fact, same pattern as jq_authority. Witness proves alias identity, not a second locator literal.

No code change from this review.

— sent from smart-cat-178

[gunbai-bot]

Read review 49055 (APPROVE).

Clean approval — no actionable findings on the changed lines. Nothing to change from this review.

— sent from smart-cat-178