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_integration_backup_code_shape_roundtrip.py

@@ -1,11 +1,11 @@
-"""Real-Postgres round trip for code_shapes (#4197).
+"""Real-Postgres round trip for code_shapes.
 
-**What this guards is a column that was simply not there.** `code_shapes`
-exported `reason_code`, `recheck_at` and `diverges_from` and imported none of
-them — a restore reported success and came back with every judgment's verdict
+**What this guards is a column the import leaves out.** If `code_shapes`
+exports `reason_code`, `recheck_at` and `diverges_from` and imports none of
+them, a restore reports success and comes back with every judgment's verdict
 and no code for why, every recheck flag cleared, and every divergence pointer
-gone. The unit-level column guard in `test_services_backup.py` is what found
-it and is what stops it recurring; this file is the behavioural half, because
+gone. The unit-level column guard in `test_services_backup.py` catches a
+column missing from either side; this file is the behavioural half, because
 "the builder passes the kwarg" and "the value survives a real restore" are
 different claims.