Adds the primitives a future magic-sets rewriter will compose:
dl-magic-rel-name rel adornment → "magic_<rel>^<adornment>"
dl-magic-lit rel adn bound-args → magic literal as SX list
dl-bound-args lit adornment → bound-position arg values
Rewriter algorithm (worklist over (rel, adornment) pairs,
generating seed, propagation, and adorned-rule outputs) is still
TODO — these helpers are inspection-only for now.
4 new magic tests cover naming, lit construction, and bound-args
extraction (mixed/free).