redesign: complete CI overhaul for CodePrism platform

- Focus on core code intelligence features: multi-language parsing, graph storage
- Add Neo4j integration testing with proper service containers
- Test all language adapters (Rust, Python, JS, Java) with Tree-sitter
- Comprehensive MCP server testing (26 tools)
- Performance benchmarks for real-time analysis
- Remove irrelevant YAML validation and test harness focus
- Add proper security auditing and documentation validation
- Platform compatibility testing across OS and Rust versions

This CI now properly tests CodePrism as a comprehensive code analysis
platform rather than just a test harness tool.

Author: milliondreams