After 0006 renamed django_ai_* tables to django_agentic_* and dropped
the explicit db_table overrides, Django's recorded state was left
inconsistent with model state. Every consumer running makemigrations
sees Django try to auto-generate a phantom rename migration with REAL
RenameIndex + AlterModelTable operations against an already-renamed
DB — failing or no-opping depending on environment.

This migration uses SeparateDatabaseAndState with empty
database_operations to record the state changes once and for all.
No physical schema work happens; state catches up to reality.

Verified: with this migration installed, makemigrations on a
consumer project reports "No changes detected".