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 runtime governance for the sandbox and artifact store: a per-process
concurrent-session cap with least-recently-used eviction of idle sessions and a
periodic idle reaper (Celery beat), so sandbox kernels do not accumulate. The
session manager performs all backend start/stop outside its lock and tears down
the captured handle, so eviction never closes a concurrently re-opened session.
Add per-user artifact quotas (count, total bytes, and per-file size) enforced at
persistence time as a soft cap, and best-effort cleanup of per-render scratch
directories in the sandbox workspace.
Introduce artifacts and artifact_versions tables: an append-only,
pass-by-reference store with a stable identity row and immutable
versions that atomically bump current_version. Access is parent-derived
(conversation or workflow run); a CHECK enforces at least one parent and
a nullable team_id is reserved for future team scoping.
Adds the 0025_artifacts migration, ArtifactsRepository with a
parent-scoped safe getter alongside the unscoped one, and repo tests.
Alex