add FlyingLine demo

[smallsco]

Summary

Adds a Micropython m68k port of the FlyingLine demo from the "Macintosh C Programming Primer" book.

Testing

Tested using Micropython m68k 20250801 on Mac OS 7.6.

[jepler]

hm, to enforce code formatting styles on examples/ or not ..

[smallsco]

Oh, I think it might be unhappy given that the file's formatted with MacRoman text encoding and uses CR line endings 😅

[jepler]

the demo does appear in the generated dsk image and work, though, so that's good!

[smallsco]

Converted to UTF-8 encoding with LR line endings, Micropython will still run the example and now it looks nice on GitHub too!

[smallsco]

Formatting should be fixed now as well

[jepler]

Thank you!

I disabled ruff formatting of the examples, but I would like them to be in a newline style that github is able to display.