Add cookbook examples with updated callback signatures for #229, #230

Cookbook structure:
- lib/: Reusable component library (Button, StatBar, AnimationChain, etc.)
- primitives/: Demo apps for individual components
- features/: Demo apps for complex features (animation chaining, shaders)
- apps/: Complete mini-applications (calculator, dialogue system)
- automation/: Screenshot capture utilities

API signature updates applied:
- on_enter/on_exit/on_move callbacks now only receive (pos) per #230
- on_cell_enter/on_cell_exit callbacks only receive (cell_pos) per #230
- Animation chain library uses Timer-based sequencing (unaffected by #229)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

tests/cookbook/lib/__init__.py

@@ -0,0 +1,81 @@
+# McRogueFace Cookbook - Standard Widget Library
+"""
+Reusable UI widget patterns for game development.
+
+Widgets:
+    Button - Clickable button with hover/press states
+    StatBar - Horizontal bar showing current/max value (HP, mana, XP)
+    ChoiceList - Vertical list of selectable text options
+    ScrollableList - Scrolling list with arbitrary item rendering
+    TextBox - Word-wrapped text with typewriter effect
+    DialogueBox - TextBox with speaker name display
+    Modal - Overlay popup that blocks background input
+    ConfirmModal - Pre-configured yes/no modal
+    AlertModal - Pre-configured OK modal
+    ToastManager - Auto-dismissing notification popups
+    GridContainer - NxM clickable cells for inventory/slot systems
+
+Utilities:
+    AnimationChain - Sequential animation execution
+    AnimationGroup - Parallel animation execution
+    delay - Create a delay step for animation chains
+    callback - Create a callback step for animation chains
+    fade_in, fade_out - Opacity animations
+    slide_in_from_* - Slide-in animations
+    shake - Shake effect animation
+"""
+
+from .button import Button, create_button_row, create_button_column
+from .stat_bar import StatBar, create_stat_bar_group
+from .choice_list import ChoiceList, create_menu
+from .text_box import TextBox, DialogueBox
+from .scrollable_list import ScrollableList
+from .modal import Modal, ConfirmModal, AlertModal
+from .toast import Toast, ToastManager
+from .grid_container import GridContainer
+from .anim_utils import (
+    AnimationChain, AnimationGroup, AnimationSequence,
+    PropertyAnimation, DelayStep, CallbackStep,
+    delay, callback,
+    fade_in, fade_out,
+    slide_in_from_left, slide_in_from_right,
+    slide_in_from_top, slide_in_from_bottom,
+    pulse, shake
+)
+
+__all__ = [
+    # Widgets
+    'Button',
+    'create_button_row',
+    'create_button_column',
+    'StatBar',
+    'create_stat_bar_group',
+    'ChoiceList',
+    'create_menu',
+    'TextBox',
+    'DialogueBox',
+    'ScrollableList',
+    'Modal',
+    'ConfirmModal',
+    'AlertModal',
+    'Toast',
+    'ToastManager',
+    'GridContainer',
+    # Animation utilities
+    'AnimationChain',
+    'AnimationGroup',
+    'AnimationSequence',
+    'PropertyAnimation',
+    'DelayStep',
+    'CallbackStep',
+    'delay',
+    'callback',
+    'fade_in',
+    'fade_out',
+    'slide_in_from_left',
+    'slide_in_from_right',
+    'slide_in_from_top',
+    'slide_in_from_bottom',
+    'pulse',
+    'shake',
+]