When an error occurs during resumed VM execution (after perform/hs-wait),
resume_vm now checks the VM's handler_stack. If a handler exists (from a
compiled guard form's OP_PUSH_HANDLER), it unwinds frames and jumps to
the catch block — exactly like OP_RAISE. This enables try/catch across
async perform/resume boundaries.
The guard form compiles to OP_PUSH_HANDLER which lives on the vm struct
and survives across setTimeout-based async resume. Previously, errors
during resume escaped to the JS console as unhandled exceptions.
Also restored guard in the test runner (was cek-try which doesn't survive
async) and restored error-throwing assertions in run-action.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
giles
0410812420