chore(changeset): minor bump for @openai/agents-core (MCP structuredContent)

Author: SkinnnyJay

.changeset/mcp-structured-content.md

@@ -0,0 +1,14 @@
+---
+'@openai/agents-core': minor
+---
+
+feat(mcp): add structuredContent support behind `useStructuredContent`; return full CallToolResult from `callTool`
+
+- `MCPServer#callTool` now returns the full `CallToolResult` (was `content[]`), exposing optional `structuredContent`.
+- Add `useStructuredContent` option to MCP servers (stdio/streamable-http/SSE), default `false` to avoid duplicate data by default.
+- When enabled, function tool outputs include `structuredContent` (or return it alone when no `content`).
+
+Notes
+
+- Type-only breaking change for direct `callTool` consumers: use `result.content` where arrays were expected.
+- Behavior matches Python SDK feature (openai-agents-python#1150) while keeping JS outputs ergonomic (objects/arrays, no JSON stringify/parse overhead).