To package your game for distribution, you should create a zip archive containing the game's source code and assets. The game's main.lua file should be at the root of this archive.
The zip file should be renamed to pak0 (with no extension) and placed in the same directory as the Juno executable. When Juno runs it will search for the pak0 file and load it if it exists.
The dynamically linked libraries should also be included when distributing your game. On Windows these are SDL.dll and lua51.dll. The Juno executable can be renamed to the title of your game. This should result in the following files:
game_title.exe (juno executable)
pak0 (zip archive of game)
lua51.dll
SDL.dll