MSB4018 and IDE1100 Errors When Building iOS in MAUI Blazor Projects with macOS Build Host

### **Description:**

Building a **MAUI Blazor App targeting iOS** results in multiple errors including `MSB4018` and `IDE1100`, despite successful debugging. This issue does **not** repro in plain MAUI or iOS apps.

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### **Version Info:**
- .NET SDK: `8.0.100-rc.1.23423.3`
- Sdk-manifest: `8.0.100-rc.1`
- `microsoft.net.sdk.android`: `34.0.0-rc.1.432`
- `microsoft.net.sdk.ios`: `16.4.8825-net8-rc1`
- `microsoft.net.sdk.maccatalyst`: `16.4.8825-net8-rc1`
- `microsoft.net.sdk.maui`: `8.0.0-rc.1.9121`
- `microsoft.net.workload.mono.toolchain.net8`: `8.0.0-rc.1.23419.4`

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### **Steps to Reproduce:**
1. Create a **MAUI Blazor App**.
2. Pair to Mac.
3. Select **Debug/Release mode** and **iOS Device**.
4. Build the project.

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### **Observed Behavior:**

  | MAUI 7 | MAUI 8 | MAUI 9 | MAUI 10
-- | -- | -- | -- | --
iOS Simulator Build | Failed | Failed | Failed | Failed
iOS Simulator Debug | Passed | Passed | Passed | Passed
iOS Device  Build | Failed | Failed | Failed | Failed
iOS Device  Debug | Passed | Passed | Passed | Passed

Severity | Code | Description | Project | File | Line | Suppression State
-- | -- | -- | -- | -- | -- | --
Error | IDE1100 | Error reading content of source file 'C:\Users\admin\source\repos\MauiApp2blazor\MauiApp2blazor\obj\Debug\net8.0-ios\iossimulator-x64\.NETCoreApp,Version=v8.0.AssemblyAttributes.cs' -- 'Could not find file 'C:\Users\admin\source\repos\MauiApp2blazor\MauiApp2blazor\obj\Debug\net8.0-ios\iossimulator-x64\.NETCoreApp,Version=v8.0.AssemblyAttributes.cs'.'. | MauiApp2blazor (net8.0-ios) | C:\Users\admin\source\repos\MauiApp2blazor\MauiApp2blazor\obj\Debug\net8.0-ios\iossimulator-x64\.NETCoreApp,Version=v8.0.AssemblyAttributes.cs | 1 | Active
Error | IDE1100 | Error reading content of source file 'C:\Users\admin\source\repos\MauiApp2blazor\MauiApp2blazor\obj\Debug\net8.0-ios\iossimulator-x64\MauiApp2blazor.AssemblyInfo.cs' -- 'Could not find file 'C:\Users\admin\source\repos\MauiApp2blazor\MauiApp2blazor\obj\Debug\net8.0-ios\iossimulator-x64\MauiApp2blazor.AssemblyInfo.cs'.'. | MauiApp2blazor (net8.0-ios) | C:\Users\admin\source\repos\MauiApp2blazor\MauiApp2blazor\obj\Debug\net8.0-ios\iossimulator-x64\MauiApp2blazor.AssemblyInfo.cs | 1 | Active
Error | IDE1100 | Error reading content of source file 'C:\Users\admin\source\repos\MauiApp2blazor\MauiApp2blazor\obj\Debug\net8.0-ios\iossimulator-x64\MauiApp2blazor.GlobalUsings.g.cs' -- 'Could not find file 'C:\Users\admin\source\repos\MauiApp2blazor\MauiApp2blazor\obj\Debug\net8.0-ios\iossimulator-x64\MauiApp2blazor.GlobalUsings.g.cs'.'. | MauiApp2blazor (net8.0-ios) | C:\Users\admin\source\repos\MauiApp2blazor\MauiApp2blazor\obj\Debug\net8.0-ios\iossimulator-x64\MauiApp2blazor.GlobalUsings.g.cs | 1 | Active
Error | IDE1100 | Error reading content of source file 'C:\Users\admin\source\repos\MauiApp2blazor\MauiApp2blazor\obj\Debug\net8.0-ios\iossimulator-x64\MauiApp2blazor.nfloat.g.cs' -- 'Could not find file 'C:\Users\admin\source\repos\MauiApp2blazor\MauiApp2blazor\obj\Debug\net8.0-ios\iossimulator-x64\MauiApp2blazor.nfloat.g.cs'.'. | MauiApp2blazor (net8.0-ios) | C:\Users\admin\source\repos\MauiApp2blazor\MauiApp2blazor\obj\Debug\net8.0-ios\iossimulator-x64\MauiApp2blazor.nfloat.g.cs | 1 | Active
Error | MSB4018 | The "GenerateStaticWebAsssetsPropsFile" task failed unexpectedly.System.IO.DirectoryNotFoundException: Could not find a part of the path 'C:\Users\admin\source\repos\MauiApp2blazor\MauiApp2blazor\obj\Debug\net8.0-ios\iossimulator-x64\staticwebassets\msbuild.MauiApp2blazor.Microsoft.AspNetCore.StaticWebAssets.props'.   at System.IO .__Error.WinIOError(Int32 errorCode, String maybeFullPath)   at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)   at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)   at System.IO.File.InternalWriteAllBytes(String path, Byte[] bytes, Boolean checkHost)   at Microsoft.AspNetCore.StaticWebAssets.Tasks.GenerateStaticWebAsssetsPropsFile.ExecuteCore()   at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute()   at Microsoft.Build.BackEnd.TaskBuilder.d__26.MoveNext() | MauiApp2blazor | C:\Program Files\dotnet\sdk\8.0.100\Sdks\Microsoft.NET.Sdk.StaticWebAssets\targets\Microsoft.NET.Sdk.StaticWebAssets.Pack.targets | 136 |  

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### **Expected Behavior:**
- No build errors or warnings when compiling a MAUI Blazor app for iOS.

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### **Additional Notes:**
- Errors disappear after debugging.
- Rebuilding or restarting the solution sometimes resolves the issue.
- Issue consistently affects release assessments and test passes.
- Repro confirmed across multiple builds including:
- `17.8 Preview 6.0`
- `17.11.0 Preview 5.0`

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### **Discussion History:**
- Eilon Lipton confirmed repro and linked to PR https://github.com/dotnet/maui/pull/17579 as a potential fix.
- Issue appears to be related to **Static Web Assets** and **design-time build** behavior.