test(ttp): E.2.13 repository tests — TTPMixin idempotency + identity-rollup projection on dual backends
Adds tests/web/db/conftest.py with a db_backends fixture parametrizing SQLite (always) + MySQL (gated on DECNET_TEST_MYSQL_URL). Surface assertions (mixin methods present + async) GREEN today; insert_tags idempotency, identity rollup projection, attacker-rollup exclusion of NULL-attacker tags xfail-gated behind E.3.3.
This commit is contained in: