Refactor Async Callbacks with Result<T> Pattern and Improve Error Handling

[oskar-ziller]

This PR involves a thorough refactor of asynchronous callbacks and error handling mechanisms. The goal is to improve code readability, efficiency, and maintainability. Key changes include:

• Implementation of the Result pattern for asynchronous callbacks, offering a more reliable approach to manage success and error states.
• Simplification of HTTP request callback logic for improved efficiency and readability, with the TezosHttpClient now utilising the Result pattern and coroutine callbacks.
• Enhancements to OperationTracker and WalletProvider to better track blockchain operations and streamline error reporting.
• Critical fix applied to TokenContract to resolve memory leaks caused by improper event handler unsubscription.
• Cleanup of outdated debug logs and documentation updates to reflect new callback signatures and behaviors.
• Update of event names for improved clarity, such as renaming ContractCallInjected to OperationInjected, and standardization of event handling using generic events like OperationCompleted in WalletEventManager.