chore(templates): modernize dependencies, .NET 10, and .slnx migration

[Aaronontheweb]

Changes

• Version bumps: All templates now use Akka.NET 1.5.60 (C#: 1.5.59→1.5.60, F#: 1.5.38→1.5.60)
• Hosting: Microsoft.Extensions.Hosting standardized to 8.0.1 across all templates
• .NET 10 support: Added net10.0 as framework option in all 5 templates, set as default
• WebApiTemplate: Converted from .sln to .slnx (new .NET 10 default format)
• F# template fixes: Fixed postActions for proper restore/editor flow

Affected Templates

Template	Akka	Hosting	Frameworks
C# WebApi	1.5.60	1.5.60	net8.0, net9.0, net10.0
C# Console	1.5.60	1.5.60	net8.0, net9.0, net10.0
C# Streams	1.5.60	1.5.60	net8.0, net9.0, net10.0
F# Console	1.5.60	1.5.60	net8.0, net9.0, net10.0
F# Streams	1.5.60	1.5.60	net8.0, net9.0, net10.0

Details

• F# Console/Streams were severely out of date (21 minor versions behind C# on 1.5.38)
• Microsoft.Extensions.Hosting was inconsistent (8.0.0 vs 8.0.1)
• WebApiTemplate .sln path resolution bug fixed via .slnx migration