Specifically,
- directly export `modules/lib/dag.nix` instead of renaming
attributes,
- run through utilities to reuse code where possible,
- expose `lib.hm.dag.isEntry` and reuse it in
`modules/lib/types-dag.nix`,
- reuse utilities through `lib` set instead of passing imports to
functions, and
- eta reduction of `map`, `entryAnywhere`, `entryAfter` and
`entryBefore`.
This change makes use of the `extend` function inside `lib` to inject
a new `hm` field containing the Home Manager library functions. This
simplifies use of the Home Manager library in the modules and reduces
the risk of accidental infinite recursion.
PR #994
Given an inner type, the former function generates a type that expect
DAG option values. The latter function is only present to temporarily
allow the `programs.ssh.matchBlocks` to keep accepting list values.
Because `extraPackages` and `overrides` expect functions as values it
has not been possible to perform merges. This adds suitable types for
these options that allow reasonable merging.
