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_family_delivery.py

@@ -1,4 +1,4 @@
-"""How family canon reaches a session (milestone 463 step 6), without a
+"""How family canon reaches a session, without a
 database: the line enter_project carries, the skill and its triggers, and the
 pointers every other surface gives to it. Retrieval reach, the readout's
 counts and the owed answers against Postgres are in