repl-form-complete? entered the :regex state on '#' but only consumed the
'#', so the opening '"' was then read by the :regex handler as the CLOSING
quote. The regex body got scanned in :code state, and any delimiter or quote
inside it (a group like #"(a)", a char class #"[0-9]+") threw off the
paren/string count — so a one-line regex form was judged incomplete and the
REPL hung waiting for continuation lines. Consume the '#"' together.
Adds a self-checking predicate test (test/chez/repl-reader-test.clj, run via
joltc so jolt.main resolves) and an end-to-end regex REPL case in smoke.sh.
