refactor(tests): add shared CLI test helpers

Adds shared test helpers for CLI script loading and scoped core.database stubs, then converts a low-conflict pilot set of CLI tests. Part of #2523.

tests/test_gallery_cli_album_count.py

@@ -1,31 +1,12 @@
-import importlib.machinery
-import importlib.util
-import sys
-import types
-from pathlib import Path
 from types import SimpleNamespace
-from unittest.mock import MagicMock
 
-
-ROOT = Path(__file__).resolve().parents[1]
-
-
-def _load_cli(monkeypatch):
-    db = types.ModuleType("core.database")
-    db.SessionLocal = MagicMock()
-    db.GalleryImage = MagicMock()
-    db.GalleryAlbum = MagicMock()
-    monkeypatch.setitem(sys.modules, "core.database", db)
-    path = ROOT / "scripts" / "odysseus-gallery"
-    loader = importlib.machinery.SourceFileLoader("odysseus_gallery_cli", str(path))
-    spec = importlib.util.spec_from_loader(loader.name, loader)
-    module = importlib.util.module_from_spec(spec)
-    loader.exec_module(module)
-    return module
+from tests.helpers.cli_loader import load_script
+from tests.helpers.db_stubs import make_core_db_stub
 
 
 def test_album_image_count_handles_missing_relationship(monkeypatch):
-    cli = _load_cli(monkeypatch)
+    make_core_db_stub(monkeypatch, models=["GalleryImage", "GalleryAlbum"])
+    cli = load_script("odysseus-gallery")
 
     assert cli._album_image_count(SimpleNamespace(images=[1, 2])) == 2
     assert cli._album_image_count(SimpleNamespace(images=None)) == 0