feat(tests): enhance testing framework with new fixtures and end-to-end tests

- Added pytest fixtures for alembic configuration and SQLite engine to streamline database testing.
- Introduced comprehensive end-to-end tests for database workflows, covering guild onboarding and disaster recovery scenarios.
- Removed outdated README and integration tests to improve test organization and clarity.
- Updated integration and unit tests to ensure robust coverage of database operations and model functionality.
- Enhanced documentation for test organization and best practices in the README.

Author: kzndotsh

tests/README.md

@@ -164,3 +164,28 @@ def pytest_report_header(config: pytest.Config) -> str:
         f"locale={os.environ.get('LC_ALL') or os.environ.get('LANG')} "
         f"network={'allowed' if config.getoption('--allow-network') else 'blocked (unit)'}"
     )
+
+
+# -----------------------------
+# Pytest-alembic fixtures
+# -----------------------------
+
+@pytest.fixture
+def alembic_config():
+    """Configure pytest-alembic to use our migration setup."""
+    from pytest_alembic.config import Config
+
+    return Config(
+        config_options={
+            "script_location": "src/tux/database/migrations",
+        },
+    )
+
+
+@pytest.fixture
+def alembic_engine():
+    """Provide a test database engine for pytest-alembic."""
+    from sqlalchemy import create_engine
+
+    # Use SQLite for pytest-alembic tests (simpler and more reliable)
+    return create_engine("sqlite:///test_alembic.db")

tests/conftest.py

@@ -1 +1,12 @@
-# E2E tests package
+"""
+End-to-end tests for Tux database workflows.
+
+These tests simulate complete user journeys and real-world scenarios:
+- First-time bot setup workflows
+- Complete feature usage scenarios
+- Data migration between versions
+- Scalability and performance testing
+- Disaster recovery scenarios
+
+Run with: pytest --run-e2e tests/e2e/
+"""