[Phase 1] v2.0 Architecture Refactoring - Directory Structure and Core Interfaces

[gmajor-encrypt]

Summary

This PR implements the Phase 1 architecture refactoring for php-scale-codec v2.0, establishing a modern foundation for the SCALE codec library.

Changes

Directory Structure

src/
├── Bytes/          # Byte manipulation utilities
├── Encoder/        # Encoder interfaces
├── Decoder/        # Decoder interfaces
├── Types/          # Type definitions and implementations
├── Metadata/       # Metadata parsing (Phase 3)
├── Extrinsic/      # Extrinsic handling (Phase 3)
└── Exception/      # Exception classes

Core Components

• ScaleType enum - PHP 8.2 enum for all SCALE types
• TypeInterface - Core interface for all types
• EncoderInterface - Interface for encoders
• DecoderInterface - Interface for decoders
• TypeRegistry - Type registration with freeze mechanism
• TypeFactory - Factory for creating types from strings
• AbstractType - Base class for type implementations
• ScaleBytes - Refactored byte manipulation class

Exception Classes

• ScaleEncodeException - Encoding errors
• ScaleDecodeException - Decoding errors
• InvalidTypeException - Type validation errors

Tests

• ScaleBytesTest - Byte manipulation tests
• ScaleTypeTest - Enum tests
• TypeRegistryTest - Registry tests

Technical Details

• PHP 8.2+ with modern features (enums, readonly properties)
• Immutable design for ScaleBytes
• Thread-safe TypeRegistry with freeze mechanism
• PSR-12 code style
• PHPUnit 10 configuration

Task List

• Adjust directory structure
• Define core interfaces
• Define ScaleType enum using PHP 8.2
• Implement TypeRegistry
• Refactor ScaleBytes class
• Define exception classes
• Unit tests for core functionality

Related Issue

Closes #31

Next Steps

• Issue [Phase 1] Type System Refactoring #32: Type System Refactoring
• Issue [Phase 2] Basic Integer Types Implementation #33: Basic Integer Types Implementation