perf: lazy-import in CLI commands to speed up startup (#335)

src/fastapi_toolsets/fixtures/__init__.py

@@ -1,8 +1,6 @@
 """Fixture system for seeding databases with dependency resolution."""
 
-from .enum import LoadStrategy
-from .registry import Context, FixtureRegistry
-from .utils import load_fixtures, load_fixtures_by_context
+from .enum import Context, LoadStrategy
 
 __all__ = [
     "Context",
@@ -11,3 +9,20 @@ __all__ = [
     "load_fixtures",
     "load_fixtures_by_context",
 ]
+
+_LAZY = {
+    "FixtureRegistry": ".registry",
+    "load_fixtures": ".utils",
+    "load_fixtures_by_context": ".utils",
+}
+
+
+def __getattr__(name: str):
+    module_name = _LAZY.get(name)
+    if module_name is None:
+        raise AttributeError(f"module {__name__!r} has no attribute {name!r}")
+
+    import importlib
+
+    module = importlib.import_module(module_name, __name__)
+    return getattr(module, name)