docs(governance): PENDING-99 census corrected; containment's sufficiency limit named

The census arithmetic is settled by counting, not by which reading closes:
17 instances / 15 distinct, the mislocation being one defect over two instances,
so the session log was right and V2 §1.5 was wrong. My withdrawal of the
original flag was itself the error — it inferred a breakdown from a total, which
a total cannot settle. Yesterday's banked pattern: a number that matches is not
a cause; it produced two candidates and I accepted each in turn.

check_containment.py now carries the limit the PENDING-99 ruling exposed:
containment verifies that what you quoted is ACCURATE, never that you quoted
what MATTERS. An omission passes every time. The countermeasure is reading the
adjacent clauses, not a better checker.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AB3Kryoy6b1pm2Nz1DYdLh

claude/governance/check_containment.py

@@ -14,6 +14,21 @@ Every run carries POSITIVE CONTROLS: near-miss strings that must be absent. If a
 is found, the instrument is not discriminating and its passes mean nothing. An absence
 is not evidence until the instrument is shown capable of detecting presence.
 
+KNOWN LIMIT — CONTAINMENT IS NOT SUFFICIENCY.
+    This tests that what you quoted is ACCURATE. It cannot test that you quoted what
+    MATTERS. An omission passes every time, because nothing was misquoted.
+
+    Demonstrated 2026-08-05, PENDING-99: the package quoted chamber §II.3 verbatim and
+    passed 16/16 with 9/9 controls absent. The sentence that actually decided the
+    question — "What remains genuinely open... the marker's exact syntax" — sat in the
+    NEXT LINE of the same subsection, was in the executor's own read output, and was
+    never surfaced. The jurist found it on first contact with the primary text and
+    reframed the ruling. A containment proof is a floor against fabrication, never
+    evidence of adequacy.
+
+    The countermeasure is not a better checker. It is a different act: read the clauses
+    ADJACENT to every quote, and say in the package that you did.
+
 KNOWN LIMIT — THIS INSTRUMENT CANNOT VERIFY A NEGATION.
     It tests whether an exact string is present. It has no notion of polarity. So a
     sentence of the form "X does NOT hold" contains, as a literal substring, the