- Added `reimportar_e_analisar` method to `App` struct to handle reimporting and analyzing files.
- Preserved previous analysis results to restore in case of errors or empty imports.
- Updated UI to include a button for reanalyzing the current file.
- Enhanced file selection logic to allow direct processing if a compatible preset is selected.
- Refactored import logic to streamline the analysis process for both CSV and XLSX files.
- Improved user feedback with appropriate error and success messages during file operations.