Release v0.4.0: Complete Interface Parsing Implementation

🎉 Major milestone: Complete SystemVerilog interface parsing support

✨ New Features:
- Complete interface declaration parsing with signals, modports, clocking blocks
- Modport parsing with comma-separated signal lists
- Clocking block parsing with timing expressions
- Parameterized interface support
- Comprehensive AST node definitions

🔧 Enhancements:
- Enhanced parser architecture with interface integration
- Improved error handling and reporting
- Full backward compatibility maintained

🐛 Fixes:
- Resolved modport comma-separated signal parsing issue
- Enhanced signal name parsing logic

🧪 Testing:
- 117/117 tests passing (6 new interface tests added)
- Comprehensive interface test coverage
- All quality checks passing

📈 Progress:
- Phase 1 (Core Language Foundation): 90% complete
- Interface Parsing: 100% complete
- Ready for Symbol Table Management System

🤖 Generated with [Claude Code](https://claude.ai/code)