✨🍏 Add front camera mirroring option

[istornz]

Description

This PR introduce front camera mirroring option to mirror or not the front camera. This is the Dart 💙 & iOS 🍏 implementation. Android part need to be done.

Partially close #255

Checklist

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• [x] 📕 I read the Contributing page.
• [x] 🤝 I match the actual coding style.
• [x] ✅ I ran flutter analyze without any issues.

Breaking Change

• [ ] 🛠 My feature contain breaking change.

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