fix: update value object to new Dart 3.0.0 syntax

[jtdLab]

Description

Migrates Value Object to use new Dart Sealed API.
This also leads to rapid_domain beeing deprecated and removed from the project.

Related Issue(s)

Resolves #153, #144

Workaround for #38 matching latest Dart language features

Type of Change

• ✨ New feature (non-breaking change which adds functionality)
• 🛠️ Bug fix (non-breaking change which fixes an issue)
• ❌ Breaking change (fix or feature that would cause existing functionality to change)
• 🧹 Code refactor
• ✅ Build configuration change
• 📝 Documentation
• 🗑️ Chore

Checklist

• 🖌️ The code follows the style and conventions of the project
• ✔️ Tests have been added or modified to cover the changes
• 📚 Documentation has been updated if necessary
• ✅ The changes have been locally tested and verified

Additional Notes

[docs-page]

To view this pull requests documentation preview, visit the following URL:

docs.page/jtdlab/rapid~156

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