Updates documentation to highlight the app's quiz-based learning features, XP and level tracking, and database-backed persistence. Clarifies question formatting, setup steps, and troubleshooting, while removing outdated sections and project structure details to better reflect current functionality and user experience.
- Added `migrate_to_sqlite.py` to handle migration of user stats and session logs from text files to an SQLite database.
- The script reads XP, level, and total time from respective text files and saves them into the `user_stats` table in the SQLite database.
- Session logs are parsed and logged into the `session_log` table.
- Existing text files are deleted after successful migration.
- Created a new SQLite database file `rhel_learning.db` with tables for questions, user stats, and session logs.
- Introduced a new test suite for validating Unicode support in various psutil APIs, ensuring that all string outputs are correctly handled without raising UnicodeDecodeError.
- Implemented tests for Process methods such as cmdline(), cwd(), and name(), as well as disk and network-related functions.
- Added tests for handling invalid Unicode paths to verify robustness against encoding issues.
- Created a separate test suite for Windows-specific functionalities, ensuring compatibility and correctness across different system calls and APIs.
- Enhanced existing tests to cover edge cases and improve overall test coverage for psutil's handling of Unicode strings.
