docs: add comprehensive autonomous workflow guide

Creates AUTONOMOUS_WORKFLOW_GUIDE.md documenting the complete
autonomous mode workflow pattern used in this project.

Guide includes:
- Setup and configuration for 100% autonomous mode
- Zero-question decision making principles
- Immediate feedback loop (commit → push → close after each issue)
- Quality gates (tests, formatting, checkstyle)
- Issue management best practices
- Workflow patterns (sequential, parallel, loop-until-dry, hybrid)
- 4 complete example workflows with code
- Best practices and anti-patterns
- Troubleshooting common issues
- Success metrics and session reporting
- Advanced techniques (adversarial verification, completeness critic)

Benefits for other projects:
- Copy-paste initial prompt for autonomous mode
- Clear quality requirements checklist
- Workflow script templates ready to adapt
- Issue structure template
- Commit message format examples

This guide enables any project with comprehensive tests to use
Claude Code in fully autonomous mode for 3-5x faster issue resolution.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: Flossy