Add option to download everything needed for the build
We are currently downloading files in the order in which we use them.
Some files are downloaded early (files for which we need their checksum to compute some output files), while other files are downloaded just before their component is built (signature files, or files for which we already know the checksum).
We should add an option to download everything without starting the build, which should then allow someone to do the build offline.
To upload designs, you'll need to enable LFS and have admin enable hashed storage. More information