Give each produced artifact a short virtual handle - A1, A2, ... - the n-th
artifact in the conversation or workflow run (case-insensitive, not stored). The
tools return it in their results, and the edit, rewrite, and input parameters
accept either the handle or the full id. A handle resolves only within the
caller's own conversation or run, and the resolved id is still checked against
that parent before any read, so it cannot reach another tenant's artifact. This
fixes the model creating a duplicate instead of a new version when asked to
edit an artifact.
Add a code workflow node that runs code in the run-scoped sandbox session and
writes produced files as artifact references into workflow state, passing them
by reference (only id and metadata, never bytes) so downstream nodes and CEL
conditions can branch on them. Add an artifacts.* templating namespace that
resolves those references to metadata via a run-scoped lookup, available to
both the workflow engine and the prompt renderer. Extract the sandbox-to-
artifact persistence into a shared helper reused by the code node and the
code_executor tool.
Alex