Inspector for prompt nodes: executor picker (model via CustomModelDropdown,
agent, skill from discovered skills, CLI named script), auto-approve toggle,
per-node max retries, and a wait-for-user-input mode with a User input palette
preset. Task card shows a 'Needs input' badge for awaiting-user-input status;
the task modal workflow tab shows the node's question as a banner.
Add a React Flow (@xyflow/react) based WorkflowNodeEditor: a lazy-loaded modal
with a workflow list, a node palette (prompt/script/gate/merge-boundary),
drag-to-connect edges, a per-node inspector, and save with compile-validation
that surfaces non-linear graphs as a banner. Pure irToFlow/flowToIr mapping
round-trips the v1 IR plus editor layout. Reachable via a Graph editor button in
the Workflow Steps manager; mounted in AppModals behind a new modal-manager
flag. Adds a vendor-reactflow Vite chunk and a feature changeset.
