[Bug]: MCP GitHub server should allow `draft: false`

[rbren]

Is there an existing issue for the same bug? (If one exists, thumbs up or comment on the issue instead).

• [x] I have checked the existing issues.

Describe the bug and reproduction steps

Not every repo allows draft PRs. This will also allow users to tell OH to open non-draft

I think defaulting to draft: true makes sense though

OpenHands Installation

Docker command in README

OpenHands Version

No response

Operating System

None

Logs, Errors, Screenshots, and Additional Context

No response