feat: major architectural refactor

- Refactor memory system (episodic/STM/LTM with components)
- Implement complete subtitle domain (scanner, matcher, placer)
- Add YAML workflow infrastructure
- Externalize knowledge base (patterns, release groups)
- Add comprehensive testing suite
- Create manual testing CLIs

tests/infrastructure/conftest.py

@@ -0,0 +1,43 @@
+"""Fixtures for infrastructure-layer tests."""
+
+import shutil
+import tempfile
+from pathlib import Path
+
+import pytest
+
+from alfred.infrastructure.persistence import Memory, set_memory
+
+
+@pytest.fixture
+def infra_temp(tmp_path):
+    """Real folder layout: downloads (with files), movies, tv_shows, torrents."""
+    dl = tmp_path / "downloads"
+    dl.mkdir()
+    (dl / "test_movie.mkv").write_bytes(b"fake video")
+    series_dir = dl / "test_series"
+    series_dir.mkdir()
+    (series_dir / "episode1.mkv").write_bytes(b"fake episode")
+
+    (tmp_path / "movies").mkdir()
+    (tmp_path / "tv_shows").mkdir()
+    (tmp_path / "torrents").mkdir()
+    return tmp_path
+
+
+@pytest.fixture
+def memory_configured(infra_temp):
+    """Fresh Memory configured with the real workspace/library_paths API."""
+    storage = tempfile.mkdtemp()
+    mem = Memory(storage_dir=storage)
+    set_memory(mem)
+
+    mem.ltm.workspace.download = str(infra_temp / "downloads")
+    mem.ltm.workspace.torrent = str(infra_temp / "torrents")
+    mem.ltm.library_paths.set("movie", str(infra_temp / "movies"))
+    mem.ltm.library_paths.set("tv_show", str(infra_temp / "tv_shows"))
+    mem.save()
+
+    yield mem
+
+    shutil.rmtree(storage, ignore_errors=True)