1187 Make set_initial_flows() of IDE model usable with and without age resolution

[annawendler]

Changes and Information

• set_initial_flows() is now defined for both ConfirmedCasesDateEntry and ConfirmedCasesNoAgeEntry by using template argument
• Allow scale_confirmed_cases to bet set for each age group individually.
• Added tests.

Merge Request - Guideline Checklist

Please check our git workflow. Use the draft feature if the Pull Request is not yet ready to review.

Checks by code author

• Every addressed issue is linked (use the "Closes #ISSUE" keyword below)
• New code adheres to coding guidelines
• No large data files have been added (files should in sum not exceed 100 KB, avoid PDFs, Word docs, etc.)
• Tests are added for new functionality and a local test run was successful (with and without OpenMP)
• Appropriate documentation for new functionality has been added (Doxygen in the code and Markdown files if necessary)
• Proper attention to licenses, especially no new third-party software with conflicting license has been added
• (For ABM development) Checked benchmark results and ran and posted a local test above from before and after development to ensure performance is monitored.

Checks by code reviewer(s)

• Corresponding issue(s) is/are linked and addressed
• Code is clean of development artifacts (no deactivated or commented code lines, no debugging printouts, etc.)
• Appropriate unit tests have been added, CI passes, code coverage and performance is acceptable (did not decrease)
• No large data files added in the whole history of commits(files should in sum not exceed 100 KB, avoid PDFs, Word docs, etc.)
• On merge, add 2-5 lines with the changes (main added features, changed items, or corrected bugs) to the merge-commit-message. This can be taken from the briefly-list-the-changes above (best case) or the separate commit messages (worst case).

Closes #1187

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.97%. Comparing base (8958e31) to head (8d60b15).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1188      +/-   ##
==========================================
- Coverage   96.97%   96.97%   -0.01%     
==========================================
  Files         148      148              
  Lines       13718    13714       -4     
==========================================
- Hits        13303    13299       -4     
  Misses        415      415              

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.