Cursor experiments

[abrichr]

This PR adds several experiments prompting the model to identify locations in screenshots without segmentation.

This implements the following approaches:

• experiments/cursor/coords.py: Uses AI prompts to iteratively locate a target in an image by drawing concentric circles.
• experiments/cursor/direction.py: Moves a cursor towards a target using AI-driven direction and magnitude adjustments.
• experiments/cursor/grid.py: Identifies target cells in an image by overlaying a grid and using AI feedback.
• experiments/cursor/joystick.py: Adjusts a cursor's position toward a target with joystick-like AI-guided movements.
• experiments/cursor/joystick_history.py: Similar to joystick.py but tracks a longer history of movements.
• experiments/cursor/quadrant.py: Locates a target by iteratively narrowing down search areas in image quadrants.
• experiments/cursor/sample.py: Uses AI voting to find the closest cursor to a target in an image.
• experiments/cursor/search.py: Refines cursor coordinates toward a target using binary search-like AI feedback.

TODO: show example outputs for each

[abrichr]

grid.py target: "Sales"