Describe the bug
Documentation mentions the possibility of using --token for passing a token instead of OIDC auth.
It also mentions MCP_GITHUB_TOKEN but providing it doesn't seem to change the behavior either. I don't see any code that handles this.

To Reproduce
Steps to reproduce the behavior:

1. Run mcp-publisher login github --token some_token

> mcp-publisher login github --token hello
flag provided but not defined: -token
Usage of login:
  -registry string
        Registry URL (default "https://registry.modelcontextprotocol.io")

2. Alternatively, Run MCP_GITHUB_TOKEN=test mcp-publisher login github

To authenticate, please:
1. Go to: https://github.com/login/device
...

Expected behavior
The login command with the token specified should attempt to login using the token, either successfully or with an auth-related error. The current state seems to imply the only passable arguments are --registry. MCP_GITHUB_TOKEN is also not used. Either documentation needs to be updated or this token should be used.

Logs
N/A

Additional context

➜  mcp-publisher --version
2025/10/23 19:03:10 mcp-publisher 1.3.3 (commit: Homebrew, built: 2025-10-16T22:35:29Z)

We want to setup GitHub token-based login for publishing.