Release 1.0.0

feat: complete blockchain core implementation

This major commit implements a fully functional blockchain system with:

1. Core Components:

• ✅ Proof-of-Work consensus algorithm
• ✅ Transaction signing/verification
• ✅ SQLite database integration
• ✅ Repository pattern implementation

2. Key Improvements:

• 🛠 Fixed genesis block initialization
• 🔒 Added transaction validation
• 🗃 Implemented proper database schema with:
  • Blocks table
  • Transactions table (with FK to blocks)
  • Nodes table
  • Optimized indexes

3. Architectural Changes:

• 🧱 Modular structure (block.py, chain.py, transaction.py)
• 📦 Repository pattern (BlockRepository, TransactionRepository)
• 🔄 Improved chain synchronization
• 📊 Better logging system

4. Bug Fixes:

• 🐛 Fixed hash calculation issues
• 🛑 Resolved database initialization errors
• 🔄 Corrected chain validation flow

The system now properly:

• Creates and validates genesis block
• Mines new blocks with configurable difficulty
• Stores all data in SQLite with proper relations
• Validates entire chain integrity
• Handles transactions with cryptographic signing

BREAKING CHANGES:

• Database schema has been completely redesigned
• Transaction structure now requires signatures
• Block hash calculation has changed

Key Points:

1. Used feat: prefix for major new functionality

2. Organized changes into clear categories

3. Included both technical and functional descriptions

4. Added breaking changes notice

5. Used emojis for better visual scanning

6. Covered all major aspects of the changes