Add Flutter runtime information

[ueman]

📜 Description

• Fixes Report version of Flutter #416
• Relevant Flutter PR Make Flutter version information accessible at runtime flutter/flutter#140783
• Edit: It got reverted again Reverts "Make Flutter version information accessible at runtime (#140783)" flutter/flutter#163753
• Edit Edit: Let's try again: Reland "Make Flutter version information accessible at runtime (#140783)" flutter/flutter#163761

Fun fact: This fixes the oldest currently open issue

💡 Motivation and Context

#416

💚 How did you test it?

I'm not entirely sure how to test this, since Dart defines aren't mockable

📝 Checklist

• I reviewed submitted code
• I added tests to verify changes
• No new PII added or SDK only sends newly added PII if sendDefaultPii is enabled
• I updated the docs if needed
• All tests passing
• No breaking changes

🔮 Next steps

Wait until the Flutter PR is merged, then merge this.

[codecov]

Codecov Report

Attention: Patch coverage is 28.57143% with 5 lines in your changes missing coverage. Please review.

Project coverage is 88.95%. Comparing base (ea1d45d) to head (ce305a1).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
.../src/event_processor/enricher/flutter_runtime.dart	25.00%	3 Missing ⚠️
...rocessor/enricher/io_enricher_event_processor.dart	33.33%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2742      +/-   ##
==========================================
- Coverage   88.99%   88.95%   -0.04%     
==========================================
  Files         263      264       +1     
  Lines        8923     8930       +7     
==========================================
+ Hits         7941     7944       +3     
- Misses        982      986       +4     

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[buenaflor]

ohh nice! 🥳