docs(6207): migrations 0088 and 0090-0094 state their rationale in terms of the data

Milestone/step labels, record ids, the rescoped-rule date and the 296-call
measurement go; each header states what the change protects. "rule 36"
citations become the DROP + ADD practice they named.

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

alembic/versions/0090_rule_verification.py

@@ -1,5 +1,4 @@
 """a rule can carry its own check — verify_with, expires_when, verified_at
-(milestone 312 step 1)
 
 Revision ID: 0090
 Revises: 0089
@@ -11,10 +10,9 @@ know they did. A CONSTRAINT is a fact about someone else's software: a
 runner's shell, a bot's config, a tool that exists. Nobody is present when
 that goes false.
 
-Milestone 307's rulebook audit found nine stale sites. Every one was a
-constraint; not one norm had rotted. One of them had been telling every
-session to skip database-backed tests for weeks while the integration lane
-sat green in the workflow.
+What goes stale in a rulebook is the constraints, not the norms — and a
+stale constraint keeps instructing every session that loads it, long after
+the world it described has moved.
 
 Three nullable columns, so a rule can say how to check itself:
 
@@ -31,7 +29,7 @@ none of them. A null `verify_with` is not an omission — it is the honest
 marker of "this one is a decision, and there is nothing to go and check."
 That signal only works if the field stays empty wherever it belongs empty.
 
-No CHECK constraint is involved, so rule 36 does not apply here. Nothing is
+No CHECK constraint is involved. Nothing is
 backfilled: a migration cannot invent a check any more than 0088 could
 invent a trigger.
 """