feat(dotfiles): sign commits everywhere except codespaces
feat(dotfiles): sign commits everywhere except codespaces

Follow-up to parent commit. Going to do this everywhere now just to get
those shiny green "Verified" badges in as many places as possible.

Note that because I have different keys on work and personal machines,
associated with different email addresses, this means that I'm going to
start making commits using my work address (ie. this commit is made on
my work machine, with my work key, so it needs to use my work address).

wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent,wincent/wincent