Test suite modernization

tests/procgen_interactive/__init__.py

@@ -0,0 +1,29 @@
+"""Interactive Procedural Generation Demo System
+
+An educational, interactive framework for exploring procedural generation
+techniques in McRogueFace.
+
+Features:
+- 256x256 maps with click-drag pan and scroll-wheel zoom
+- Interactive parameter controls (steppers, sliders)
+- Layer visibility toggles for masks/overlays
+- Step forward/backward through generation stages
+- State snapshots for true backward navigation
+"""
+
+from .core.demo_base import ProcgenDemoBase, StepDef, LayerDef, StateSnapshot
+from .core.parameter import Parameter
+from .core.widgets import Stepper, Slider, LayerToggle
+from .core.viewport import ViewportController
+
+__all__ = [
+    'ProcgenDemoBase',
+    'StepDef',
+    'LayerDef',
+    'StateSnapshot',
+    'Parameter',
+    'Stepper',
+    'Slider',
+    'LayerToggle',
+    'ViewportController',
+]