connects #2074
This pull request refactors the MeterDataSummaryTableComponent to optimize how meter reading differences are managed and displayed. The main improvement is the introduction of a readingDifferencesMap for efficient access to comparison results, which streamlines modal interactions and UI conditionals. Additionally, some unused UI elements were removed for clarity.

Data handling and performance improvements:

• Introduced a readingDifferencesMap object to cache meter reading differences for each meter, computed once during initialization with the new computeReadingChanges() method. This avoids redundant calculations and simplifies access to differences when opening the modal.

UI logic and cleanup:

• Updated the conditional display of the "eye" icon in the summary table to depend on the presence of differences in readingDifferencesMap instead of the previous newEntries check, ensuring more accurate UI feedback.
• Removed the alert message that appeared when there were no differences between existing and imported meter readings, decluttering the UI.

Modal interaction:

• Refactored the modal-opening logic to use the precomputed differences from readingDifferencesMap, further simplifying the code and improving performance.