Summary

Updates using statements that reference the old namespace throughout the entire solution.

Changes

• Added UpdateUsingStatementsInSolution to scan all projects in the solution
• Added UpdateUsingStatementsInFile to handle all using statement variants:
  • using OldName; → using NewName;
  • using OldName.SubNamespace; → using NewName.SubNamespace;
  • using Alias = OldName.Type; → using Alias = NewName.Type;
  • global using OldName; → global using NewName;
  • using static OldName.ClassName; → using static NewName.ClassName;
• Recursively handles solution folders

Test plan

• Rename a project that other projects have using statements for
• Verify using OldName; statements are updated to using NewName;
• Verify nested usings like using OldName.Sub; are updated
• Verify using aliases are updated
• Verify solution still builds after rename

Closes #9