swarm-ui: a todo switched from clear to upsert drops its prefix flag

frontend/packages/swarm-ui/src/pages/notifications/FlowDraft.ts

@@ -200,6 +200,20 @@ export function reparent(
   };
 }
 
+// A todo with its op switched. A clear carries no text, and only a clear may
+// be a prefix, so each is reset where the new op has no place for it.
+export function withOp(
+  node: Extract<FlowNode, { kind: "todo" }>,
+  op: "upsert" | "clear",
+): Extract<FlowNode, { kind: "todo" }> {
+  return {
+    ...node,
+    op,
+    text: op === "clear" ? "" : node.text,
+    prefix: op === "clear" ? node.prefix : false,
+  };
+}
+
 // The node with `next.id` swapped for `next`. A node keeps its place and its
 // kind-class: the source stays the source, and nothing with children becomes
 // a todo.

frontend/packages/swarm-ui/src/pages/notifications/FlowEditorPage.tsx

@@ -185,7 +185,7 @@ export function FlowEditorPage({
             reload and drop my edits
           </Button>
           <Button onClick={() => void load(true)}>
-            keep my edits on top of the latest
+            keep my edits (replaces this flow's latest version)
           </Button>
         </div>
       ) : null}

frontend/packages/swarm-ui/src/pages/notifications/NodeInspector.tsx

@@ -16,6 +16,7 @@ import {
   replaceNode,
   type Edit,
   type Limits,
+  withOp,
 } from "./FlowDraft.js";
 import {
   kindValues,
@@ -237,14 +238,7 @@ function TodoFields({
         label="op"
         value={node.op}
         options={opList}
-        onChange={(op) =>
-          onChange({
-            ...node,
-            op: op as TodoNode["op"],
-            // A clear carries no text.
-            text: op === "clear" ? "" : node.text,
-          })
-        }
+        onChange={(op) => onChange(withOp(node, op as TodoNode["op"]))}
       />
       <SelectField
         id={`${keyPrefix}-to-kind`}