Feature Request: Headless/Programmatic Authentication for Q CLI in Server Environments

**Use Case:**
Running Q CLI in headless EC2 environments for infrastructure automation tools

**Current Problem:**
- Q CLI requires interactive browser authentication
- Cannot use Q CLI + MCP integration on servers
- Blocks enterprise automation workflows
- No support for AWS IAM roles or service principals for q login

**Requested Feature:**
- Headless authentication mode (API keys, service accounts)
- Non-interactive login option for CI/CD and server deployments
- Maintain full MCP integration capabilities
- Enterprise customers need IAM role authentication for Q CLI, just like every other AWS service, to avoid session management and comply with security
policies.

**Business Impact:**
- Supports DevOps workflows
- Increases Q CLI adoption in production environments