Add Basic Authentication support for on-premises Business Central

[bimiscusi]

Summary

This PR adds support for HTTP Basic authentication to enable the MCP server to connect to on-premises Business Central servers. Previously, only Azure CLI and client credentials authentication methods were supported, limiting usage to cloud-based deployments.

Key Changes

• Authentication Method: Added basic as a new authentication type alongside existing azure_cli and client_credentials options
• Configuration: Added two new environment variables:
  • BC_USERNAME: Business Central username
  • BC_PASSWORD: Web service access key or password
• Client Implementation: Updated BusinessCentralClient to handle Basic auth by encoding credentials in Base64 and setting the Authorization header
• Validation: Added environment variable validation to ensure required credentials are provided when using basic auth
• Documentation:
  • Updated README with basic auth configuration examples
  • Added comprehensive setup instructions for on-premises servers
  • Updated authentication recommendation to guide users based on deployment type (cloud vs on-premises)
• Smithery Config: Added UI configuration fields for username and password in smithery.yaml
• Version Bump: Updated package version from 0.1.1 to 0.1.2

Implementation Details

• Basic auth header is computed once during client initialization and reused for all requests, avoiding repeated encoding
• The implementation follows the same pattern as token-based auth, with a unified request method that handles both authentication types
• On-premises server URLs typically use port 7048 with format: https://{server}:{port}/{instance}/api/v2.0
• Web service access keys are recommended over passwords for improved security

https://claude.ai/code/session_01KhpN4Ho9C1xWtYPJhhygZe