While digging into test-load-sci, add genuinely-missing clojure.core fns:
doall/dorun/run!/tree-seq, key/val/map-entry?, rand-nth/replicate/
bounded-count/counted?/reversible?/seqable?, nat-int?/pos-int?/neg-int?/
double?/float?/ratio?/decimal?/rational?/numerator/denominator, list*,
special-symbol?/record?, promise/deliver, comparator/completing/halt-when/
ensure-reduced/unreduced, keyword-identical?/object?/tagged-literal/re-groups.
Fix a real pre-existing bug: iterating a map (first/seq/map/filter/reduce/vec/
realize-for-iteration) returned keys or values instead of [k v] entries.
Map literals are Janet structs (not phm), which several paths mishandled.
Now first/seq/realize-for-iteration yield entries for both structs and phms,
matching Clojure — e.g. (vec {:a 1}) => [[:a 1]], (map key m), (reduce f init m).
Tests: conformance 218/218 (+12), features 78/78, jank 120. Advances the SCI
bootstrap further (its clojure.core aggregation map resolves more symbols).
