Persists client edits to the workflow table as a separate file so AI regeneration never overwrites user changes. The client sends a single page (same shape as the filter endpoint response) together with the offset/limit that produced it. The handler loads the current table (the edited file when it already exists, otherwise the AI-generated base), re-applies the default sort so positions line up with what the client saw, overwrites the [offset, offset+len) window with the incoming rows, and writes the result back to the edited file. Rows outside the window are preserved. The GET/filter endpoints always return this edited version when it exists.