C++ additions:
- get_global_bounds(): returns bounds in screen coordinates
- contains_point(x, y): hit test using global bounds
Python properties (on all UIDrawable types):
- bounds: (x, y, w, h) tuple in local coordinates
- global_bounds: (x, y, w, h) tuple in screen coordinates
These enable the mouse event system (#140, #141, #142) by providing
a way to determine which drawable is under the mouse cursor.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
