fix[Calibration Trends]: Imporve performance for loading data

Description

• Fix bug when no constants found for all modules.
• Refactor code to increase readability
• Improve calibration trends performance:
  • Cache utils.get_data() to avoid reloading same file each time.
  • Move to multiprocessing to avoid GIL and increase performance.

Changes Made

Screenshots

Below are screenshots for loading 10 CCVs for 16 AGIPD modules for 1 calibration.

Before improving the performance:

After improving the performance:

Related Issues

Tests

Additional Notes

Merge Request Checklist

• Code follows project coding guidelines.
• Documentation reflects the changes made.
• Unit tests are added or updated to cover the changes.
• The application runs without errors and the new functionality works as expected.