feat: copy imported files

[ddanielsantos]

• chore: update ignored files
• feat: copy imported files and update their path

[ddanielsantos]

part of #8

I consider this extremely important now (need to update #4)

[ddanielsantos]

given this deck file:

this is the generated slide

get-slide-content is the culprit here, it doesnt know how to handle custom imports, it was created only with builtin ones in mind

[ddanielsantos]

TBD in another PR