[Feat/tests] Added Unit & Integration Tests

[RedExtreme12]

Added Unit & Integration Tests, changed CI/Release workflows with tests running.

• Added Unit Tests to verify our code drives pika correctly, with the broker fully mocked (no live RabbitMQ needed):
  • consumer — dispatches deliveries to the handler, refreshes DB connections, and on handler error nacks without requeue (requeue=False).
  • producer — publishes with mandatory=True, and drops & rebuilds a dead channel to republish.
  • connections — connection manager builds parameters, lazily opens, and resets channels.
  • registries — consumer & setup registries register and resolve correctly per alias.
  • commands — setup_rabbitmq_topology and start_consumers wire up the right calls.
  • apps / utils — app config bootstraps managers & registries; helpers behave as expected.
• Added Integration Tests to prove broker-side consequences the mocked unit tests can't:
  • roundtrip — real producer → real consumer via default & direct exchanges.
  • dlx — handler exception actually dead-letters into the DLQ.
  • reconnect — consumer & producer self-heal after a broker-side connection kill.
  • mandatory — unroutable publish raises UnroutableError; passive declare of a missing queue raises ChannelClosedByBroker.
  • consumer_lifecycle — graceful stop, prefetch_count back-pressure, multi-alias vhost isolation.
  • commands — setup_rabbitmq_topology (idempotent) and start_consumers (in a real subprocess).
• CI & tooling
  • github/workflows/ci.yml — unit tests across Python 3.10–3.14 + integration job against a rabbitmq:4.3.1-management service container.
• publish.yml reuses the CI test jobs before release.
• docker-compose.yml — local RabbitMQ (with management plugin) for running integration tests.
• pytest/integration marker config and dev deps in pyproject.toml;

[Wern-rm]

It needs to be finalized