Styled/Dashed Lines for Shapes

[anesthetice]

The goal of this PR is to allow users to modify the style of shapes, e.g. dashed lines, dotted lines, dotted shapes, etc. Furthermore to unify UI elements of the Shaper menu.

The current implementation could be made more efficient in the future if a pull request to add a sync flag in Piet gets merged.

https://github.com/user-attachments/assets/851bf6a1-b211-430a-a6ea-5d72f40fd487

fixes #852 fixes #375

Cons of the current implementation

• piet::StrokeStyle built on every call to draw_composed()
• the use of a SmoothOptionPrecursor and ShapeStylePrecursor

Pros of the current implementation

• minor impact on file size
• don't have to wait for a piet PR to be merged