Add MCP agent client setup support

docs/superpowers/plans/2026-05-14-research-agent-mcp-discover-data.md

@@ -903,14 +903,16 @@ Add this test after the `dictionary_search` registration test:
         limit: 5,
       }),
     ).resolves.toMatchObject({
-      structuredContent: [
-        {
-          kind: 'table',
-          id: 'public.orders',
-          connectionId: 'warehouse',
-          tableRef: { catalog: null, db: 'public', name: 'orders' },
-        },
-      ],
+      structuredContent: {
+        refs: [
+          {
+            kind: 'table',
+            id: 'public.orders',
+            connectionId: 'warehouse',
+            tableRef: { catalog: null, db: 'public', name: 'orders' },
+          },
+        ],
+      },
     });
     expect(discover.search).toHaveBeenCalledWith({
       query: 'orders',

docs/superpowers/specs/2026-05-14-research-agent-mcp-tools-design.md

@@ -143,7 +143,9 @@ or `entity_details` tools.
 }
 ```
 
-**Output:** array of refs, each:
+**Output:** `{ refs: Ref[] }` — the MCP protocol requires `structuredContent`
+to be a JSON object, so the array of matches is wrapped under `refs`. Each
+ref is shaped:
 
 ```typescript
 {