Multiple canvas draws in loops

[gb119]

Description:

In src/stonerplots/context/multiple_plot.py:369-410, multiple figure.canvas.draw() calls within loops could be expensive for complex figures.

Impact:

• Slower rendering for complex multi-panel figures
• Each draw triggers a full re-render
• Noticeable with many subplots or complex visualizations

Recommendation:

Consider batching drawing operations - collect all changes then draw once:

# Instead of:
for ax in axes:
    modify(ax)
    figure.canvas.draw()  # Draw after each modification

# Consider:
for ax in axes:
    modify(ax)
figure.canvas.draw()  # Draw once at the end

Important: Verify this doesn't break intended behavior - some operations may require intermediate draws for measurements or layout calculations.