fix(hosted-wasm): load OIDC AuthenticationService script before Blazor startup

[Copilot]

Purpose

Hosted WASM startup could fail with Could not find 'AuthenticationService.init' ('AuthenticationService' was undefined) when OIDC auth initialized. This PR ensures the required Microsoft authentication runtime script is present in the hosted entry page before Blazor bootstraps.

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Scope

Select one primary concern:

• Bug fix (behavior change)
• Refactor (no behavior change)
• Documentation update
• Formatting / code cleanup
• Dependency / build update
• New feature

If this PR includes multiple unrelated concerns, please split it before requesting review.

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Description

Problem

Hosted WASM (Elsa.Studio.Host.HostedWasm) did not include the WebAssembly auth static asset required by RemoteAuthenticationService / RemoteAuthenticatorView, resulting in AuthenticationService.init missing at runtime.

Solution

• Hosted entry page script wiring
  • Added Microsoft’s auth script include to /Pages/_Host.cshtml before _framework/blazor.webassembly.js.
• Startup compatibility
  • Aligns hosted WASM boot sequence with the standalone WASM host and module expectations for OIDC.

<script src="_content/Microsoft.AspNetCore.Components.WebAssembly.Authentication/AuthenticationService.js"></script>
<script src="_framework/blazor.webassembly.js" autostart="false"></script>

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Verification

Steps:

1. Run hosted WASM host (Elsa.Studio.Host.HostedWasm) with Authentication:Provider=OpenIdConnect.
2. Open the app and trigger authentication state resolution (normal startup path is sufficient).
3. Confirm no AuthenticationService.init JS interop error appears.

Expected outcome:
OIDC auth initializes without AuthenticationService-undefined runtime failures.

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Screenshots / Recordings (if applicable)

N/A (startup/runtime wiring fix, no UI change).

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Commit Convention

We recommend using conventional commit prefixes:

• fix: – Bug fixes (behavior change)
• feat: – New features
• refactor: – Code changes without behavior change
• docs: – Documentation updates
• chore: – Maintenance, tooling, or dependency updates
• test: – Test additions or modifications

Clear commit messages make reviews easier and history more meaningful.

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Checklist

• The PR is focused on a single concern
• Commit messages follow the recommended convention
• Tests added or updated (if applicable)
• Documentation updated (if applicable)
• No unrelated cleanup included
• All tests pass