Added three new projects: `DigitalData.TaskFlow.Domain`,
`DigitalData.TaskFlow.Application`, and
`DigitalData.TaskFlow.Infrastructure` to the solution.
Updated the solution file to include their paths, GUIDs,
build configurations, and nested structure.
Each project targets `.NET 8.0`, uses `Microsoft.NET.Sdk`,
and enables implicit usings and nullable reference types.
Introduced an `ExtensibilityGlobals` section with a
`SolutionGuid` for better solution management.
TekH
41a395af99