Add Postgres table adapter with TableRepositoryInterface.

Introduce PostgresAdapter for dict-based row CRUD via psycopg3, including config, lazy exports, unit/integration tests with testcontainers, and an example UserTableRepository.

Co-authored-by: Cursor <[email protected]>

python_repositories/__init__.py

@@ -6,17 +6,19 @@ from typing import TYPE_CHECKING
 
 # Interfaces are always available; they have no optional backend dependencies.
 from . import adapters
-from .config import MinioConfig, RedisConfig, load_dotenv
+from .config import MinioConfig, PostgresConfig, RedisConfig, load_dotenv
 from .interfaces import (
     ConnectionAwareInterface,
     ContextAwareInterface,
     JsonRepositoryInterface,
     ObjectRepositoryInterface,
+    TableRepositoryInterface,
 )
 
 # Adapters are imported only for static type checkers; runtime loading is delegated below.
 if TYPE_CHECKING:
     from .adapters.minio_adapter import MinioAdapter as MinioAdapter
+    from .adapters.postgres_adapter import PostgresAdapter as PostgresAdapter
     from .adapters.redis_adapter import RedisAdapter as RedisAdapter
 
 __all__ = [
@@ -25,7 +27,9 @@ __all__ = [
     "JsonRepositoryInterface",
     "MinioConfig",
     "ObjectRepositoryInterface",
+    "PostgresConfig",
     "RedisConfig",
+    "TableRepositoryInterface",
     "load_dotenv",
     *adapters.__all__,
 ]