Fix React UI tool call example

[matteo8p]

In the callServerTool of the React widget example, we pass in the parameter city. However, the parameter is supposed to be location. See this line in server.ts:

https://github.com/modelcontextprotocol/ext-apps/blob/main/examples/simple-server/server.ts#L164

See tool call action working;
https://github.com/user-attachments/assets/1f060616-bd37-4f74-bc77-3fe25af3e64a

Motivation and Context

Fixes the tool call action

How Has This Been Tested?

Tested in MCPJam. Confirmed that the tool call action is working as expected

Breaking Changes

NA

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Documentation
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have added or updated documentation as needed

Additional context