Enhance crowdfund functionality and environment configuration
- Added optional environment variables for Sancho API URL and custom slot configuration to improve flexibility in testing and deployment. - Refactored crowdfund components to utilize standardized fetch methods for transactions and UTxOs, enhancing consistency and error handling. - Updated contribution fetching logic to accurately reflect contributions and withdrawals, including improved handling of transaction types. - Introduced charting capabilities for visualizing funding progress over time, enhancing user experience in crowdfund information display. - Streamlined wallet data loading processes and improved error handling across various components for better reliability.