Install project-local agent guidance without overwriting unmanaged content.
mix agent_kit.installSame reconciliation as mix agent_kit.sync. Configuration is read from
:elixir_agent_kit in Mix.Project.config/0; when that entry exists it is the
source of truth, otherwise the recorded selection in .elixir-agent-kit/state.tsv
is kept. --agents codex,claude,generic and --skills ID,ID override it for one
run; --dry-run lists the paths without writing. Fails when the dependency's
library is incomplete. No task starts your application or calls a model.