feat(drift): add devops-drift-set for state checks

[kpassapk]

Compare live command output against a declared expectation as unordered line sets, for org state-check blocks where file drift does not apply. First use: systemd unit checks in aly-infra server files.

[kpassapk]

Doesn't seem the right place to put a set comparison. Here is an example with bb:

#+name: a
#+begin_example
apple
banana
cherry
#+end_example

#+name: b
#+begin_example
apple
cherry
fig
#+end_example

#+begin_src bb :var a=a b=b 
  (let [sa (set (str/split-lines a))
        sb (set (str/split-lines b))]
    {:only-a (clojure.set/difference sa sb)
     :only-b (clojure.set/difference sb sa)})
#+end_src

#+RESULTS:
| :only-a | banana | :only-b | fig |