docs(6209): forty test files — design cascade and stylesheet, embeddings, family canon, forge, backup round trips, inception, placement, platforms, moments, rule move and verification, search scope, facets

Module and test docstrings state what is pinned without the record number
or step that introduced it. Incident accounts become the failure shape in
the present tense: the pipefail head, the code_shapes import, the export
order, the facet dialects, the cross-kind repeat, the write-once kind.

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

tests/test_create_tools_disambiguate.py

@@ -1,12 +1,11 @@
-"""Every create_* tool says what it is NOT for (#3123).
+"""Every create_* tool says what it is NOT for.
 
 WHY THIS EXISTS
 
 Scribe's record kinds are reached for interchangeably — a note written where
 a task was owed, a rule written where a snippet belonged — and the moment of
 choice is the only moment a correction is cheap. The tool docstring IS the
-agent-facing contract (rule 119 puts product guidance there and nowhere
-else), so a docstring that only documents parameters answers "how do I call
+agent-facing contract (product guidance lives there and nowhere else), so a docstring that only documents parameters answers "how do I call
 this" while leaving "should I be calling this at all" unasked.
 
 The gap was lopsided before this: `create_rule` and `start_planning` both