Fix incorrect x axis date labels

[eldcn]

Fix incorrect x axis date labels

♻️ Current situation & Problem

• We have had several iterations on fixing the correct date formatting for x axis in health charts, e.g. (Chart scaling #78 and Investigate: Chart XValues too precise #92). This due to how the charts library expects the values. We display the dates in the x axis and must supply the corresponding double value to the chart. We have tried in the last iterations to transform the values to reduce the distance between values in order to also reduce the spreading of the graph.
• In the last iteration we were mapping a Date to a double of the pattern YYYY,DD where DD was calculated as day of year / 365 rounded to max 2 decimal places and were mapping it back to a date format the label. Chart library on the other hand, was expecting the decimal places to be rounded to max 2 places. Rounding was causing the issue and we were not able to derive the initial date correctly

Adapted the approach to:

1. Given a list of measurements and their corresponding dates, pick the oldest date
2. Map the dates as follows for the selected time range:
   • Daily: Diff in days from the oldest date
   • Weekly: Diff in weeks from the oldest date
   • Monthly: Diff in months from the oldest date
3. The diff is used ultimately as the x value, e.g. for daily time range:

2025-01-01 → 0
2025-01-04 → 3
2025-01-06 → 5
2025-01-13 → 12
2025-02-14 → 44

4. The library supplies us back the value and expects a formatted label text for it, e.g. 5 -> we derive the initial date as 2025-01-06 and ultimately format it as Jan 06
5. Unit tests added to cover all three time ranges
6. Recording:

chart_x_labels.mp4

⚙️ Release Notes

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✅ Testing

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[codecov]

Codecov Report

Attention: Patch coverage is 57.40741% with 23 lines in your changes missing coverage. Please review.

Project coverage is 40.72%. Comparing base (b98ea73) to head (d835d6a).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...ord/bdh/engagehf/health/symptoms/SymptomsScreen.kt	0.00%	17 Missing ⚠️
...tanford/bdh/engagehf/health/HealthUiStateMapper.kt	85.30%	5 Missing ⚠️
...ford/bdh/engagehf/health/components/HealthChart.kt	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main     #171      +/-   ##
============================================
+ Coverage     40.54%   40.72%   +0.18%     
- Complexity      858      866       +8     
============================================
  Files           299      299              
  Lines         11421    11434      +13     
  Branches       1716     1723       +7     
============================================
+ Hits           4630     4655      +25     
+ Misses         6326     6319       -7     
+ Partials        465      460       -5     

Flag	Coverage Δ
uitests	36.01% <ø> (+0.03%)	⬆️
unittests	32.10% <57.41%> (+0.19%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
.../engagehf/health/symptoms/SymptomsUiStateMapper.kt	94.90% <100.00%> (ø)
.../bdh/engagehf/health/symptoms/SymptomsViewModel.kt	94.26% <100.00%> (ø)
...ford/bdh/engagehf/health/components/HealthChart.kt	0.00% <0.00%> (ø)
...tanford/bdh/engagehf/health/HealthUiStateMapper.kt	68.58% <85.30%> (+10.88%)	⬆️
...ord/bdh/engagehf/health/symptoms/SymptomsScreen.kt	0.00% <0.00%> (ø)

... and 1 file with indirect coverage changes

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[PSchmiedmayer]

Really like the new visualizations @eldcn; thank you for the additional tests and getting this in place! 🚀