docs(6209): forge, dedup, tuning, registry, reply shapes and discipline, checkpoint, lesson kind tests

Eight more test files state their properties without issue, milestone,
rule and decision numbers. The tuning and suspension notes describe the
symptom a shipped default or a late ledger produces instead of one
install's dated readings; the reply-discipline and checkpoint docstrings
state the failure they prevent instead of the session that measured it.
test_empty_selector_is_the_rule_115_baseline is renamed for what it
checks: the no-forge baseline.

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

tests/test_retrieval_registry.py

@@ -1,10 +1,10 @@
-"""Every retrieval point is declared, derived from the CALL SITES (#3431).
+"""Every retrieval point is declared, derived from the CALL SITES.
 
 WHY AST AND NOT GREP, demonstrated rather than asserted. Two of the sources in
 this system reach their recorder as `source=SOURCE` through a module-level
 constant — `wide_net` and `preference_slot` — so a grep for `source="` finds
 neither. A registry test built on that grep would pass while being blind to
-two arms, which is the narrowing #3191 warns about: a check that looks
+two arms — a check that looks
 thorough and quietly covers less than it claims.
 
 So the extractor below parses each module, resolves module-level string
@@ -35,13 +35,13 @@ from scribe.services.retrieval_surfaces import SURFACES
 SRC = Path(__file__).resolve().parents[1] / "src"
 
 # The recorders, plus the one FORWARDER. `rules_payload` takes a `source` and
-# passes it to `record_rule_surfaced` on its caller's behalf (snippet #2858),
+# passes it to `record_rule_surfaced` on its caller's behalf,
 # so its callers are the real declaration site and a scan of recorders alone
 # would miss every ambient rule surfacing.
 RECORDERS = {
     "record_retrieval", "record_surfaced", "record_pulled",
     "record_rule_surfaced", "record_rule_pulled", "rules_payload",
-    # The rulings arm (#4769): its two recorders, and `rulings_for_paths`,
+    # The rulings arm: its two recorders, and `rulings_for_paths`,
     # which forwards its caller's `source` the way `rules_payload` does.
     "record_system_surfaced", "record_system_pulled", "rulings_for_paths",
 }
@@ -90,7 +90,7 @@ def call_sites() -> tuple[dict[str, set[str]], list[str]]:
 
 
 def test_the_extractor_finds_something() -> None:
-    """The guard has to be able to fail (rule 167).
+    """The guard has to be able to fail.
 
     An extractor that silently matched nothing would make every assertion
     below vacuously true — a green suite proving the opposite of what it
@@ -130,7 +130,7 @@ def test_every_unresolved_call_site_is_declared() -> None:
     # EQUALITY, not prefix. The first spelling of this compared against a
     # prefix that could never match — the paths begin `scribe/` — so the check
     # passed by matching nothing, which is the failure mode a guard is most
-    # likely to have and least likely to show (rule 167).
+    # likely to have and least likely to show.
     undeclared = sorted({u for u in unresolved if u not in FAN_OUT_SITES})
     assert not undeclared, (
         "these call sites pass `source` as a value this test cannot resolve, "
@@ -157,7 +157,7 @@ def test_every_tunable_surface_is_also_a_registered_point() -> None:
 
 
 def test_a_quiet_point_says_why() -> None:
-    """A justified silence must carry its justification (#2475).
+    """A justified silence must carry its justification.
 
     Without the reason the reader cannot tell a decision from an oversight,
     which is the whole difference this field exists to record.