Atualiza o workflow de CI para melhorar a verificação de cobertura de…

[moreirawebmaster]

… código, implementando a extração de linhas totais e cobertas a partir do arquivo LCOV. Adiciona mensagens de feedback para diferentes cenários de cobertura, incluindo tratamento de ausência de dados de cobertura.

📋 Description

Brief description of changes and motivation behind them.

🔄 Type of Change

• 🐛 Bug fix (non-breaking change which fixes an issue)
• ✨ New feature (non-breaking change which adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to not work as expected)
• 📚 Documentation update
• 🧪 Test improvement
• 🔧 Refactoring (no functional changes)
• 🎨 Style changes (formatting, naming, etc.)

🧪 Testing

• Tests pass locally (flutter test)
• Coverage remains high (./scripts/test_coverage.sh)
• Pana analysis passes (./scripts/pana_analysis.sh)
• Added tests for new functionality
• Updated documentation if needed

📱 Platform Testing

• Tested on Android
• Tested on iOS
• Works on physical devices
• Works on emulator/simulator

🔍 Code Quality

• Code follows style guidelines
• Self-review completed
• Added necessary code comments
• No new warnings or errors
• Performance impact considered

📋 Checklist

• 📝 Updated CHANGELOG.md
• 📚 Updated README if needed
• 🏷️ Updated version in pubspec.yaml (if applicable)
• 🧪 All tests pass
• 📊 Coverage percentage maintained or improved
• 🔍 Pana score maintained or improved

🔗 Related Issues

Closes #(issue number)
Addresses #(issue number)
Related to #(issue number)

📸 Screenshots (if applicable)

Add screenshots to help reviewers understand the changes.

🚨 Breaking Changes

If this PR contains breaking changes, list them here with migration guide:

// Before
final old = OldAPI();

// After  
final new = NewAPI();

📋 Additional Notes

Any additional information, concerns, or considerations for reviewers.