fix(wizard): match real EA2 apply-batch contract

Wizard was sending ops in the SDX-era shape:
  { collection, op: 'insert', flow_key, _key, ... }
with actor + flow_key duplicated at the request root.

Real EA2 contract (verified against ea2.baseline.svc/openapi.json):
  POST /api/ea2/apply-batch
  body: { request_id (8..128), ops: BatchOp[] (1..500), description? }
  additionalProperties=false at request root
  ops are a discriminated union by 'op':
    create / update / delete (nodes by coll+key+data)
    create_edge / delete_edge (edges by edge_coll+from+to)
  actor/tenant resolved from Bearer token, not body.

Adds typed CreateOp/UpdateOp/DeleteOp/CreateEdgeOp/DeleteEdgeOp + wizardApi.ops
helpers (createNode, createEdge, publishFlow) so call sites don't have to
remember the discriminator shape.

Wizard.handleStructureSave + handlePublish updated to use the helpers.

src/scenes/Wizard.tsx

@@ -103,24 +103,19 @@ export default function Wizard() {
     if (!draft.flowKey || !actor) return;
     setWorking(true);
     try {
-      const ops: BatchOperation[] = draft.nodes.map(n => ({
-        collection: "ea2_node",
-        op: "insert",
-        flow_key: draft.flowKey,
-        ...n
-      }));
-      
-      // Link them sequentially
-      for (let i = 0; i < draft.nodes.length - 1; i++) {
-        ops.push({
-          collection: "ea2_edge",
-          op: "insert",
-          flow_key: draft.flowKey,
-          _from: `ea2_node/${draft.nodes[i]._key}`,
-          _to: `ea2_node/${draft.nodes[i+1]._key}`,
-          kind: "next"
-        });
-      }
+      const ops: BatchOperation[] = [
+        ...draft.nodes.map(n =>
+          wizardApi.ops.createNode(draft.flowKey!, {
+            _key: n._key,
+            display_name: n.display_name,
+            dispatch_kind: n.dispatch_kind,
+            agent_capability: n.agent_capability,
+          })
+        ),
+        ...draft.nodes.slice(0, -1).map((n, i) =>
+          wizardApi.ops.createEdge(draft.flowKey!, n._key, draft.nodes[i + 1]._key, "next")
+        ),
+      ];
 
       await wizardApi.applyBatch(draft.flowKey, ops, actor);
       updateDraft({ step: "Generate" });
@@ -170,14 +165,7 @@ export default function Wizard() {
     if (!draft.flowKey || !actor) return;
     setWorking(true);
     try {
-      const ops: BatchOperation[] = [
-        {
-          collection: "ea2_flow",
-          op: "update",
-          _key: draft.flowKey,
-          status: "published"
-        }
-      ];
+      const ops: BatchOperation[] = [wizardApi.ops.publishFlow(draft.flowKey)];
       await wizardApi.applyBatch(draft.flowKey, ops, actor);
       updateDraft({ step: "Publish" });
       setPublishedKey(draft.flowKey);