What changed

• Raised mutation coverage in backend domain and application tests.
• Added targeted tests for Result<T>, PagedResult<T>, authentication, movie handlers, and domain value objects/entities.
• Fixed the mutation test wrapper and added dotnet-tools.json so Stryker runs from the source project context reliably.
• Updated the README routing note to match the current SPA entry points.

Validation

• dotnet test backend/tests/SmartMovieCatalog.Domain.Tests/SmartMovieCatalog.Domain.Tests.csproj --no-restore
• dotnet test backend/tests/SmartMovieCatalog.Application.Tests/SmartMovieCatalog.Application.Tests.csproj --no-restore
• powershell -NoProfile -ExecutionPolicy Bypass -File .\eng\scripts\test-mutation.ps1 -Scope both

Result

• Domain mutation score: 89.36%
• Application mutation score: 94.74%