LibraryConfigurationMiddleware invokes the pipeline twice on malformed libraryId

[umerfaruk]

Summary

When the `libraryId` route segment fails to parse as an int, the middleware calls `next(context)` but doesn't return, then falls through and calls `next(context)` again at the end of the method.

Details

`LibraryConfigurationMiddleware.Invoke` (src/Inshapardaz.Api/Infrastructure/Middleware/LibraryConfigurationMiddleware.cs:18-45):
```csharp
else if (!int.TryParse(libraryIdValue, out libraryId))
{
await next(context); // no return here
}

var library = await _libraryRepository.GetLibraryById(libraryId, CancellationToken.None);
...
await next(context); // executes again
```

Impact

For a request with a malformed `libraryId` and a side-effecting HTTP method (POST/PUT/DELETE), the controller action — and any command it dispatches — runs twice. This could mean duplicate writes, duplicate emails sent, etc.

Suggested fix

Add a `return;` immediately after the first `await next(context);` call in that branch.