MCP ms365: OAuth URL contains duplicate 'prompt' parameter

Bug Description

The MCP ms365 authentication flow generates an OAuth URL with the prompt parameter duplicated, causing Microsoft Azure AD to reject the request.

Error Message

AADSTS9000411: The request is not properly formatted. The parameter 'prompt' is duplicated.

Steps to Reproduce

1. In Claude Code CLI, trigger ms365 authentication
2. The generated URL contains both prompt=select_account AND prompt=consent
3. Microsoft rejects with AADSTS9000411

Environment

• Claude Code CLI (terminal)
• macOS
• Note: MCP ms365 works in Claude Cowork (desktop)