Migrate chapter 4 common solution to .NET 10 and add central package management

[meaboutsoftware]

📋 Description

This PR migrates the Fitnet.Common solution to .NET 10, introduces Central Package Management for better dependency consistency, and updates the package workflow to align with the main solution's configuration.

Key Changes:

• Migrated all Fitnet.Common projects from .NET 9 to .NET 10
• Implemented Central Package Management using Directory.Packages.props
• Updated package workflow to use .NET 10.0.x (previously 9.0.x)
• Corrected NUGET_SOURCE_NAME to EvolutionaryArchitecture for consistency
• Replaced reusable action with direct dotnet nuget add source command
• Updated all NuGet packages to their latest .NET 10 compatible versions

Workflow-Specific Changes:
Unlike the main solution workflow which needed to authenticate against an existing local nuget.config, the package workflow uses dotnet nuget add source since it runs on a fresh runner without pre-existing NuGet sources and the Fitnet.Common directory doesn't contain a local nuget.config.

📦 PR Includes

• Feature added 🆕 (Central Package Management)
• Bug fix 🐛 (Workflow SDK version mismatch)
• Code refactor 🔄 (.NET 10 migration, package consolidation)
• Documentation update 📚
• Tests added/updated 🧪
• Other: Infrastructure upgrade to .NET 10

🚫 PR Does Not Include

• Breaking changes ❌
• Major architectural changes 🏗️
• Unrelated features/tasks 🚫

💡 Additional Notes

Central Package Management Benefits:

• Single source of truth for all package versions in Directory.Packages.props
• Eliminates version conflicts across Fitnet.Common projects
• Simplifies dependency updates and maintenance
• Aligns with .NET best practices and modern solution structure

Workflow Updates:

• All jobs now use .NET 10.0.x SDK for consistency with main solution
• NUGET_SOURCE_NAME standardized to EvolutionaryArchitecture across all workflows
• Simplified authentication using direct dotnet nuget add source (appropriate for pack job which runs on fresh runner)

Consistency Across Solutions:
Both the main Fitnet solution and Fitnet.Common solution now follow the same patterns:

• ✅ .NET 10 migration complete
• ✅ Central Package Management implemented
• ✅ Workflows updated and aligned
• ✅ NuGet source naming standardized