The dummy schema still stamped the old migration version

CI builds the engine's test database from spec/dummy/db/schema.rb, and that file
still said `version: 2026_08_19_000001`. Loading it marks every migration up to
that number as applied — which no longer includes device_grants at
20260819093412 — so rspec aborted with a pending migration before running
anything, and both the push and the tag pipeline failed.

It passed on my machine because I had renumbered the row in the live test
database by hand and never re-dumped the schema. Verified this time the way CI
does it: dropped the database, `rake app:db:test:prepare` from schema.rb, 227
examples green.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

libs/ruby/warp_engine/spec/dummy/db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[8.1].define(version: 2026_08_19_000001) do
+ActiveRecord::Schema[8.1].define(version: 2026_08_19_093412) do
   create_table "application_tokens", id: { type: :bigint, unsigned: true }, charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.datetime "created_at", precision: 3
     t.datetime "deleted_at", precision: 3