47 new compile-mode tests: collections, math, predicates, comparison,
seq operations (map/filter/reduce/take/drop), special forms (let/if/loop/
try/quote), macros (defn/when/and/or/fn/if-let), complex nesting.
Bugs fixed:
- emit-vector-expr: use (tuple ...) instead of bare tuple
(Janet eval treats bare tuples as function calls)
- make-symbol: / at position 0 → unqualified symbol
(was parsing as {:ns "" :name ""})
- core-renames: add missing fn? entry
