docs: test improvements for v1.2.7 (#430)

* feat: implement logging to file for stability tests

* feat: enhance stability test logging with real-time output

* feat: add max-retries option to stability test for improved error handling

* refactor: streamline transaction search and error handling in e2e tests

- Replaced direct block polling with /search/transactions for improved efficiency in locating transactions.
- Enhanced error logging and debugging information for transaction retrieval processes.
- Updated test cases to reflect changes in transaction search method and improved assertion messages for clarity.
- Improved output formatting for error details in test reports.

* feat: enhance ADA balance management and logging in stake operations

- Introduced internal helper methods for fetching ADA balance and validating balance changes.
- Improved logging for stake operations, including detailed balance information and error handling.
- Updated test scenarios to utilize new balance validation methods, ensuring accurate tracking of ADA transactions.
- Enhanced output formatting for clarity in transaction success and failure messages.

* refactor: restructure e2e tests and client architecture

- Removed outdated e2e test files and configurations to streamline the testing framework.
- Introduced a new directory structure for better organization of test utilities and client components.
- Enhanced logging and error handling mechanisms across the Rosetta client and test utilities.
- Updated README and configuration files to reflect the new structure and setup instructions.
- Improved overall code readability and maintainability by consolidating related functionalities.

* chore: expand concurrency levels in the stability test from 200 to 500, allowing for a broader range of performance assessments

Author: linconvidal