Avoid remote agent warning when no remote authority is configured

Does this issue occur when all extensions are disabled?: Yes

- VS Code Version: Web build from current main (3414ff55cc8)
- OS Version: macOS 15.7.9

Steps to Reproduce:

1. Start VS Code Web (e.g. from sources `./scripts/code-web.sh`, or via the `@vscode/test-web` node module)
2. Open the browser developer tools console.
3. Observe these messages:

```text
INFO [AgentHost:remote] Initializing (remoteAuthority=none)
WARN [AgentHost:remote] No remote agent connection available. Not connecting.
```

I found it strange that AgentHost is mentioned in the log of a browser only VS Code.
Also interesting that it's possible to open the chat view.

https://github.com/microsoft/vscode/blob/3414ff55cc8/src/vs/workbench/services/agentHost/browser/editorRemoteAgentHostServiceClient.ts#L82-L88

I would expect `No remote agent connection available. Not connecting.` to be logged only when `IWorkbenchEnvironmentService.remoteAuthority` is set but no connection is available. When `remoteAuthority` is unset, returning without a warning is the normal path.