Align passkey guidance with the .NET 11 Blazor template

[rolandVi]

Documents dotnet/aspnetcore#65343, dotnet/aspnetcore#65752, dotnet/aspnetcore#67539 and dotnet/aspnetcore#67589.

The passkey articles had drifted from the Blazor Web App template, so a .NET 11 reader following them copies the .NET 10 flow.

Versioned JavaScript

The .NET 10 samples stay as they are. The .NET 11 versions drop the headers argument, which the template stopped sending in dotnet/aspnetcore#67589 when it moved to the fetch-metadata CSRF middleware. Those endpoints are still validated, just by the middleware instead of a token header, so nothing loses protection here.

The rest

• The RedirectToInvalidUser snippet doesn't compile any more, because Update Blazor templates to use TempData aspnetcore#65752 removed RedirectToWithStatus from the template. .NET 10 already ships the method, so the section was wrong in both versions. Dropped it.
• Added PasskeyAuthenticators.cs to the model classes list, missing since Infer passkey display name from AAGUID aspnetcore#65343.
• Documented that PasskeySignInAsync returns SignInResult.Failed on expired session state instead of throwing, per SignInManager: return SignInResult.Failed for expired passkey session challenge aspnetcore#67539.
• Fixed a source link whose line range had moved.

Two things I left out on purpose: the creation options URL moving to /Account/Manage/, and PasskeyOperation gaining Reauthenticate. Both are .NET 12 only, and there's no aspnetcore-12.0 moniker yet, so gated content would render for nobody.

One fix outside the drift: the "locate the Blazor script tag" snippet was missing @Assets[...], which is wrong in every version.

Checked every sample against release/10.0, release/11.0 and main.

---

Internal previews

File	Preview link
aspnetcore/security/authentication/passkeys/blazor.md	Learn preview
aspnetcore/security/authentication/passkeys/index.md	Learn preview

Build report

[guardrex]

Thanks, @rolandVi ... Let me try and get back to you tomorrow (Tuesday). I'm ⛏️😅 at the moment on a doc overhaul.