Update to .NET 10

- Update all project runtime targets
- Update all dependencies
  - NOTE: Using Npgsql.EntityFrameworkCore.PostgreSQL RTM build from MyGet
- Delete unused pubxml files (they were made redundant by recent workflow changes)
- Replace Libation.sln with Libation.slnx

.github/workflows/build.yml

@@ -12,7 +12,7 @@ on:
         required: true
       dotnet-version:
         type: string
-        default: "9.x"
+        default: "10.x"
         description: ".NET version to target"
       run-unit-tests:
         type: boolean