Large build contexts due to not respecting `.gitignore`

[nebulatgs]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

Trying to build a local directory with large folders like NodeJS node_modules or Rust target will take a long time, since Nixpacks will attempt to copy those folders into a tempdir and into the build container.

To reproduce

Create a new Rust project
Run cargo build once locally
Run nixpacks build . and see how it takes a long time

Expected behavior

Nixpacks would respect the .gitignore file and only copy the files that are needed.

Environment

Windows 11
Nixpacks v0.3.8

[coffee-cup]

I think we can copy .gitignore to .dockerignore so that those files are not copied into the image.

[nebulatgs]

I think we can copy .gitignore to .dockerignore so that those files are not copied into the image.

The issue is the nixpacks temp directory, we copy everything there and it takes forever. I have a fix almost ready.