## Scope: engine only
Behind the existing `IS_WORKFLOW_VERSION_IN_CORE_ENABLED` flag (**off by
default**), `getWorkflowVersionOrFail` sources a version's `trigger` /
`steps` / `status` from `core.workflowVersion` instead of the workspace
row. That covers its 11 call sites: workflow build, validation, schema,
run, and trigger dispatch.
**The UI is not switched here.** `useWorkflowVersion` and the content
fetch in `useWorkflowWithCurrentVersion` still go through generic object
CRUD against the workspace columns. That work needs the client to stop
treating the workspace record as the home for content, and is planned
separately around `flowComponentState` (the jotai state the builder
already reads from). It is the read that must land before the workspace
`trigger` / `steps` columns can be dropped.
## Why an overlay, not a repository swap
`core.workflowVersion` is a content-only projection: its own `id` (not
the workspace version id), `workflowId`, `triggers[]`, `steps[]`,
`status`. No `name`, no `position`. So core cannot fully back the
entity.
The flip is therefore an overlay: identity, name and position stay from
the workspace row, and only content comes from core (`triggers[0] ->
trigger`).
## Reversibility
Falls back to workspace content when the flag is off (default), when the
version has no `coreWorkflowVersionId` soft-ref, or when the core row is
missing. Merging changes nothing until the flag is enabled per
workspace, and it can be flipped back at any time.
## Verification
- `nx typecheck twenty-server` green, `oxfmt` + `oxlint --type-aware`
green
- Unit test covering four branches: flag off, flag on with the core row
present (overlays content **and** preserves `id` / `name` from the
workspace row), flag on with the core row missing (falls back on
`trigger`, `steps` and `status`), flag on with no soft-ref (skips the
core read)
## Enablement gate
Do not enable the flag in any workspace until the drift dashboard
reports zero drift for `core.workflowVersion` and legacy drift is
repaired. Enabling before that turns latent drift into live dispatch
behaviour.
Thomas Trompette
198e3969df