Configuration is powered by ortho_config. The most common global option is
the default repository, which lets numeric pull request references resolve to
owner/repo:
vk --repo leynos/vk pr 191
The same value can be supplied through VK_REPO or a configuration file:
repo = "leynos/vk"
Set VK_CONFIG_PATH or pass --config-path to choose a specific configuration
file. See the Ortho Config users' guide for the
full configuration model.