---

This section details on the original issue you should resolve

<issue_title>RZ1000 triggered when Utf8 strings literals are used</issue_title>
<issue_description>## Description

Using Utf8 string literals in a razor page trigger

RZ1000
Unterminated string literal.  Strings that start with a quotation mark (") must be terminated before the end of the line.  However, strings that start with @ and a quotation mark (@") can span multiple lines.

PR that introduced this (?): #11086

Repro

Create a ASP.NET Core Web App (Razor Pages) project and add the following code to Index.cshtml:

@page
@using System.Text
@model IndexModel

<div class="text-center">
    @{
        ReadOnlySpan<byte> span = "hello"u8;    // <- here's the error location
    }

    <p>@Encoding.UTF8.GetString(span)</p>
</div>

(yeah I know it's nonsense, but stripped down from a real project were Utf8 literals makes sense).

Expected behavior

Utf8 string literals are supported and don't trigger RZ1000.

Workaround

Update csproj with

<PropertyGroup>
    <NoWarn>$(NoWarn);RZ1000</NoWarn>
</PropertyGroup>
```</issue_description>

<agent_instructions>Please update the parser so that C# UTF-8 strings are supported. Create compiler integration tests, using the example repro in this issue, but also make sure to include coverage for .cshtml and .razor files, and for `u8` strings in `@code` and/or `@functions` blocks, `@{ .. }` blocks, and `@( ... )` blocks etc.</agent_instructions>

## Comments on the Issue (you are @copilot in this section)

<comments>
</comments>