v1.3.1 - Fix Entity Unavailability

🐛 Bug Fix

Fixed Entity Unavailability During Reconfiguration

• Problem: When adding new cryptocurrencies via reconfiguration, existing entities became unavailable with error "Cette entité n'est plus fournie par l'intégration"
• Root Cause: Optional fields (ID, unit_of_measurement) were not preserved during reconfiguration, changing entity unique_id
• Solution: Preserve optional fields from existing configuration to maintain entity stability

📝 What's Changed

• Modified config_flow.py: Preserve CONF_ID and CONF_UNIT_OF_MEASUREMENT during reconfiguration
• Changed optional field schema from suggested_value to default for reliable value submission
• Version bump: 1.3.0 → 1.3.1

🔧 Technical Details

• Use or operator to fallback to existing values when optional fields are empty
• Ensure unique_id stability across reconfigurations

---

🤖 Generated with Claude Code