Add QueueRepositoryInterface with memory and file-backed adapters.

Provide a generic disk-backed FIFO queue with configurable path, retention, and dedup keys so consumers can buffer items across restarts without optional extras.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/unit/adapters_test.py

@@ -46,6 +46,8 @@ assert JsonRepositoryInterface is not None
 assert "python_repositories.adapters.redis_adapter" not in sys.modules
 assert "python_repositories.adapters.minio_adapter" not in sys.modules
 assert "python_repositories.adapters.postgres_adapter" not in sys.modules
+assert "python_repositories.adapters.memory_queue_adapter" not in sys.modules
+assert "python_repositories.adapters.file_backed_queue_adapter" not in sys.modules
 """
     result = subprocess.run(
         [sys.executable, "-c", script],
@@ -59,11 +61,19 @@ assert "python_repositories.adapters.postgres_adapter" not in sys.modules
 
 def test_lazy_adapter_load_succeeds_when_extra_present() -> None:
     """Adapters load when their optional dependencies are installed."""
-    from python_repositories import MinioAdapter, PostgresAdapter, RedisAdapter
+    from python_repositories import (
+        FileBackedQueueAdapter,
+        MemoryQueueAdapter,
+        MinioAdapter,
+        PostgresAdapter,
+        RedisAdapter,
+    )
 
     assert RedisAdapter.__name__ == "RedisAdapter"
     assert MinioAdapter.__name__ == "MinioAdapter"
     assert PostgresAdapter.__name__ == "PostgresAdapter"
+    assert MemoryQueueAdapter.__name__ == "MemoryQueueAdapter"
+    assert FileBackedQueueAdapter.__name__ == "FileBackedQueueAdapter"
 
 
 def test_redis_adapter_import_error_without_extra() -> None:
@@ -149,9 +159,13 @@ def test_adapters_dir_exposes_lazy_exports() -> None:
     """dir(adapters) includes lazy adapter names for tab completion."""
     import python_repositories.adapters as adapters
 
-    assert {"RedisAdapter", "MinioAdapter", "PostgresAdapter"}.issubset(
-        set(dir(adapters))
-    )
+    assert {
+        "RedisAdapter",
+        "MinioAdapter",
+        "PostgresAdapter",
+        "MemoryQueueAdapter",
+        "FileBackedQueueAdapter",
+    }.issubset(set(dir(adapters)))
 
 
 def test_adapters_getattr_raises_for_unknown() -> None:
@@ -167,3 +181,5 @@ def test_top_level_dir_exposes_lazy_exports() -> None:
     assert "RedisAdapter" in dir(python_repositories)
     assert "MinioAdapter" in dir(python_repositories)
     assert "PostgresAdapter" in dir(python_repositories)
+    assert "MemoryQueueAdapter" in dir(python_repositories)
+    assert "FileBackedQueueAdapter" in dir(python_repositories)