feat: Add Fragment API for TON topups, Telegram Premium purchases, and Stars transactions

- Implemented Fragment API with methods for TON topups, Premium gifts, and Stars purchases.
- Created configuration management using environment variables.
- Added detailed README documentation for installation, configuration, and usage.
- Developed utility classes for API client, wallet linking, and transaction processing.
- Included example usage in main.py for easy demonstration of API functionalities.
- Updated requirements.txt with necessary dependencies.

.gitignore

@@ -0,0 +1,25 @@
+# Python
+__pycache__/
+*.pyc
+*.pyo
+*.pyd
+.Python
+
+# Virtual environments
+.venv/
+venv/
+
+# IDE
+.idea/
+.vscode/
+
+# Logs
+logs/
+*.log
+
+# Environment variables
+.env
+
+# System files
+.DS_Store
+Thumbs.db