jolt's own throw sites raised untyped Chez conditions with the class name buried
in an English message, so (class e) reported the opaque :object and only a broad
catch worked:
(class (try (Long/parseLong "xyz") (catch Throwable e e))) => :object
; JVM: java.lang.NumberFormatException
Raise typed throwables (jolt-host-throwable) at the Long/Double parse and
StringTokenizer sites so (class e) / .getMessage / a specific catch all reflect
the real class. And fold the exception supertype table (exception-parent) into
the one class graph: exception-isa? now resolves the simple name to its graph key
and asks jch-isa?, so exceptions and every other class share a single hierarchy.
Runtime only, no re-mint. make test green (0 new/stale), +2 corpus rows.