Fix Issue #20 & #14: Enhanced MCP Protocol & Duplicate Detection

- Issue #20: MCP Protocol Version Compatibility
  * Added comprehensive version negotiation with fallback support
  * Implemented client type detection (Claude, Cursor, VS Code)
  * Added client-specific optimizations and timeout handling
  * Enhanced protocol compliance with JSON-RPC 2.0
  * Added comprehensive test coverage for version negotiation

- Issue #14: Improved Duplicate Detection
  * Replaced basic Jaccard coefficient with AST-based analysis
  * Added semantic understanding with pattern recognition
  * Implemented multiple duplicate types (exact, structural, semantic)
  * Added intelligent refactoring suggestions with effort estimation
  * Enhanced with confidence scoring and complexity analysis
  * Added language-specific analyzers for Python/JS/TS

Closes #20 #14

Author: milliondreams