Improved Nix package + project dependencies for VSCode

[luisnquin]

Changes

default.nix

Support for:

• .desktop file + icon
• Program sounds
• tomatonoise

notify.{c,h}

• Refactored notify function

shell.nix

• Added program inputs in order to be used by CLANG compiler of VSCode

Observation

I haven't tried the Mac version of the notifications, but the cmd string created is like this: osascript -e 'display notification "󱎫 Work!" with title "You need to focus"'

So check it out, It looks good for me