internal/

Package build renders Dockerfiles for layered presets, computes deterministic image tags, and invokes `docker build` to materialize them.

Package config loads drun presets from the embedded defaults and an optional user override at $XDG_CONFIG_HOME/drun/presets.yaml (falling back to ~/.config/drun/presets.yaml).

Package run assembles and executes the `docker run` command for a preset.