Evaluate declared emission cadence and close AUDIT-WP-0009 (T05)

The contract T05 waited on is published: info-tech-canon
emission-cadence wire schema 0.1, contract digest b08b4d95fc4b0bd3.
A source-owned declaration now travels as emission_cadence on the
sender registration; expected-rate entries raise below_declared_cadence
on /v1/stream-findings from the same counts /v1/reconciliation returns.
heartbeat-or-reconciliation entries are validated and left to T04/T06.

Records the observer evaluation of net-kingdom's local-identity
declaration: structurally clean, not operationally evaluated, one
heartbeat event_class mapping incompatibility.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Assistant: claude-code
Assistant-Model: opus
Assistant-Process: 151986@bnt-lap001
Assistant-Session: ccd02b6b-80ae-48e5-8cad-9c8f74d21a67

audit_core/senders.py

@@ -22,6 +22,7 @@ from pathlib import Path
 from typing import Any, Iterable
 
 from audit_core.redaction import POLICIES, POLICY_REDACT
+from audit_core.emission_cadence import parse_declaration
 
 WILDCARD = "*"
 
@@ -71,9 +72,9 @@ class SenderIdentity:
     # §9.6 heartbeat declaration (AUDIT-WP-0009-T04): event class -> the
     # longest gap, in seconds, that is not yet a finding.
     #
-    # This is deliberately NOT the §17 emission-cadence schema that T05 waits
-    # on. Cadence describes a stream's expected *rate* and belongs to Taxonomy;
-    # this is a registration property saying how often a source promises to say
+    # This is deliberately NOT the emission-cadence declaration (T05, below).
+    # Cadence describes a stream's expected *rate* and its shape is
+    # info-tech-canon's; this is a registration property saying how often a source promises to say
     # "nothing to report" for a class that may legitimately be silent. The two
     # are complementary and audit-core is not inventing a competing rate shape.
     #
@@ -82,6 +83,10 @@ class SenderIdentity:
     # nothing about the quiet, security-relevant one — which is the only case
     # heartbeats exist for.
     heartbeat_classes: tuple[tuple[str, int], ...] = ()
+    # The source-owned emission cadence declaration (AUDIT-WP-0009-T05),
+    # parsed from info-tech-canon wire schema 0.1 — the §17 shape the heartbeat
+    # field above deliberately did not invent. ``None`` means undeclared.
+    emission_cadence: Any = None
 
     def __post_init__(self) -> None:
         if not self.name:
@@ -144,6 +149,9 @@ class SenderIdentity:
             "completeness_claimed": False,
             "completeness_trade": self.completeness_trade,
             "heartbeat_classes": dict(self.heartbeat_classes),
+            "emission_cadence": (
+                self.emission_cadence.summary() if self.emission_cadence else None
+            ),
             "detection_surface": None,
         }
 
@@ -315,6 +323,7 @@ def _apply_scope_overlay(
                     else identity.completeness_trade
                 ),
                 heartbeat_classes=_overlay_heartbeats(identity, extra),
+                emission_cadence=_overlay_cadence(identity, extra),
             )
         )
     return merged
@@ -370,6 +379,22 @@ def _overlay_heartbeats(
     return tuple(sorted(proposed.items()))
 
 
+def _overlay_cadence(identity: SenderIdentity, extra: dict[str, Any]) -> Any:
+    """The overlay may not touch an emission cadence declaration.
+
+    A declaration is the source's, pinned to a contract digest; a partial
+    overlay has no sound merge with it, and replacing it wholesale could widen
+    a window or drop a class without anyone deciding to. Changing it is a
+    change to the Secret-backed registration.
+    """
+    if "emission_cadence" in extra:
+        raise ValueError(
+            f"sender {identity.name!r}: the scope overlay may not set or change "
+            "emission_cadence"
+        )
+    return identity.emission_cadence
+
+
 def _parse_identities(raw: str) -> list[SenderIdentity]:
     try:
         entries = json.loads(raw)
@@ -396,6 +421,11 @@ def _identity_from(entry: Any) -> SenderIdentity:
         evidence_kind=str(entry.get("evidence_kind", EVIDENCE_ATTRIBUTIVE)),
         completeness_trade=_clean_trade(entry.get("completeness_trade")),
         heartbeat_classes=_heartbeat_classes(entry.get("heartbeat_classes")),
+        emission_cadence=(
+            parse_declaration(entry["emission_cadence"])
+            if entry.get("emission_cadence") is not None
+            else None
+        ),
     )