Adds regex-compile/test/exec/match-all/replace/replace-fn/split/source/flags.
Opaque dict handle {:__regex__ true :id :source :flags}; compiled Re.re
cached in a primitives-local table. Replacement supports $&, $1-$9, $$.
Flags: i (CASELESS), m (MULTILINE), s (DOTALL). g is a runtime flag handled
in replace. u (unicode) skipped for now.
Unblocks js-on-sx's regex-platform-override! hook — the JS RegExp shim can
now delegate to real regex instead of the substring stub.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
giles
81022784bc