docs(6209): wide net, startup, stamps, slippage, miss route and parity tests

Eight more test files state the property they pin as a present-tense
fact. Incident narratives (a dated storage stall, a week of zero tuning
events, a two-project poisoned ledger, a twenty-site owner audit) become
the failure shape each test defends; one-install figures that name a rule
become a general worked example with the calibration numbers kept. The
family-grouping regression guard is renamed for what it checks.

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

tests/test_divergence_meaning_gate.py

@@ -1,21 +1,18 @@
-"""A semantic MISS is not evidence, and the divergence check never reads one (#4208).
+"""A semantic MISS is not evidence, and the divergence check never reads one.
 
-WHAT THIS IS ABOUT. #4204 gave the divergence check a structural gate, which
-silenced one of the five false prompts it was filed for. The other four are
-`def` helpers beside an `async def` service canon — callables beside a
-callable — and differ from #2793's acceptance case (a hand-rolled sync
-`confirmDanger` where an async confirm helper is canon) only by the JOB they
-do. A signature does not carry a job.
+WHAT THIS IS ABOUT. The divergence check's structural gate separates a type
+from a callable canon. `def` helpers beside an `async def` service canon —
+callables beside a callable — differ from the readout's acceptance case (a
+hand-rolled sync `confirmDanger` where an async confirm helper is canon) only
+by the JOB they do. A signature does not carry a job.
 
-#4208 tried meaning: store the proposer's semantic "compared, nothing cleared
-the floor" and let it withdraw the prompt. Measured live on 2026-09-22 it
-cannot discriminate. Judged instances of the service-unit canon score 0.68–
-0.71 against it at best, most below 0.66; helpers score 0.66–0.75 against
-snippets unrelated to them. The then-floor of 0.8 was reached by nothing, so
-the "miss" fired for nearly every body — the real divergence silenced exactly
-as the helper was. The gate was removed; the prompt asks and the judge
-answers. The same measurement moved the arm's floor down to the write-path
-hint's: 0.8 was sized for proposals nobody reads, and it proposed 0 of 150.
+Meaning cannot withdraw the prompt either. Judged instances of a service-unit
+canon score 0.68–0.71 against it at best, most below 0.66; helpers score
+0.66–0.75 against snippets unrelated to them. No floor separates the two, so a
+"compared, nothing cleared the floor" miss fires for nearly every body,
+silencing the real divergence exactly as it silences the helper. So the prompt
+asks and the judge answers, and the arm proposes at the write-path hint's
+floor: one sized for proposals nobody reads proposes almost nothing.
 
 These tests pin what stayed: the arm proposes on a hit and says nothing on a
 miss, the divergence check does not consult it, and the capped pass reads new
@@ -32,8 +29,8 @@ from scribe.services import shape_ledger
 from scribe.services.shape_ledger import _semantic_canon
 
 # Comfortably over WRITEPATH_MIN_CODE_CHARS (48 non-whitespace characters), so
-# these tests exercise the comparison rather than the substance guard. One of
-# #4204's four survivors, quoted rather than invented.
+# these tests exercise the comparison rather than the substance guard. A real
+# helper body, quoted rather than invented.
 BODY = (
     "def is_registered(source: str) -> bool:\n"
     "    return source in _REGISTRY and _REGISTRY[source].enabled\n"
@@ -87,7 +84,7 @@ async def test_a_body_too_thin_to_embed_spends_no_embedding() -> None:
 
 
 async def test_no_allowed_canon_spends_no_search() -> None:
-    """The language-family gate (#2871) empties the allowed set routinely."""
+    """The language-family gate empties the allowed set routinely."""
     mock = _hits()
     with _patch(mock):
         assert await _semantic_canon(1, BODY, set()) is None
@@ -97,7 +94,7 @@ async def test_no_allowed_canon_spends_no_search() -> None:
 async def test_the_arm_proposes_at_the_write_path_floor() -> None:
     """It asks the write-path hint's question of the same documents, so it
     uses that surface's floor — not a stricter private one that yields no
-    proposals for the judge to weigh (#4208)."""
+    proposals for the judge to weigh."""
     from scribe.services.plugin_context import WRITEPATH_DEFAULT_THRESHOLD
 
     mock = _hits()
@@ -111,14 +108,14 @@ async def test_the_arm_proposes_at_the_write_path_floor() -> None:
 
 def test_the_divergence_check_does_not_read_the_proposal_basis() -> None:
     """The retired gate keyed on `proposal_basis`. Asserted on the function's
-    structure (rule 167): any attribute read of it inside `flag_divergence` is
+    structure: any attribute read of it inside `flag_divergence` is
     the miss being consulted again, whatever the constant is called."""
     tree = ast.parse(textwrap.dedent(inspect.getsource(shape_ledger.flag_divergence)))
     reads = [n for n in ast.walk(tree)
              if isinstance(n, ast.Attribute) and n.attr == "proposal_basis"]
     assert not reads, (
         "flag_divergence reads proposal_basis — a semantic miss is 'cannot "
-        "tell' at the arm's floor (#4208), never 'not the canon'"
+        "tell' at the arm's floor, never 'not the canon'"
     )