LSPs are initialized before running the sessionStart hook

### Describe the bug

I am writing a hook that will help keep my LSP install updated. However, I cannot update the LSP because copilot is launching it before running hooks. This seems out of order to me.

```
2026-05-04T23:34:50.080Z [DEBUG] LSP csharp server for Q:\source\TestConsole2: [Program] Language server initialized
...
2026-05-04T23:35:04.709Z [DEBUG] Executing hook: ./.github/hooks/scripts/session-start.ps1
```

### Affected version

GitHub Copilot CLI 1.0.41-0

### Steps to reproduce the behavior

1. Add a lsp.json
2. Configure an LSP
3. Add a hooks/copilot-hooks.json
4. Configure a session-start hook that runs a session-start.ps1
5. Add a session-start.ps1 which prints "Hello"
6. Start Copilot
7. Observe the logs

### Expected behavior

I expected that the session-start.ps1 would be complete prior to initializing LSPs.

### Additional context

_No response_

Reproduce the ordering with lsp.json, hooks/copilot-hooks.json, and session-start.ps1, then compare the startup logs around LSP initialization and the session-start hook. Done means the session-start hook completes before the configured LSP is initialized.

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