Support for Custom Request Headers

[Sano7707]

Summary

This PR adds support for passing custom HTTP request headers (for example, Authorization tokens or custom user/session headers) to the Trino query client and schema providers.

Motivation

In authenticated or proxy-secured Trino environments, requests often require authentication tokens or identity-related headers. Previously, these headers could not be configured through the UI component, making it difficult to integrate with secured deployments.

This change enables host applications to provide custom headers through the main QueryEditor component. The supplied headers are propagated to:

• Query execution requests
• Schema and catalog discovery requests

When no custom headers are provided, the client maintains the existing behavior and falls back to the default header:

X-Trino-User: system

Example Usage

import { QueryEditor } from 'trino-query-ui';

function App() {
  return (
    <QueryEditor
      height={800}
      requestHeaders={{
        Authorization: 'Bearer your-jwt-token-here',
        'X-Trino-User': 'custom-user-context',
      }}
    />
  );
}

[cla-bot]

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