Approved design for first-class array-valued local variables across the
panel-logic (TS) and control-logic (Go) engines: array StateVar declarations
(dynamic/capped/fixed sizing), an array-aware expression language shared by
both engines, sizing-policy-aware mutation nodes (unifying the existing
accumulate/export/clear arrays), persistence, and widget binding.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>