[Bug] editor.foldLevel1 does not fold first region if it's the first line

Reproducible in vscode.dev or in VS Code Desktop?

• Not reproducible in vscode.dev or VS Code Desktop

Reproducible in the monaco editor playground?

• Not reproducible in the monaco editor playground

Monaco Editor Playground Link

Here the first region does not collapse:

https://microsoft.github.io/monaco-editor/playground.html?source=v0.52.2#XQAAAAKAAQAAAAAAAABBqQkHQ5NjdMjwa-jY7SIQ9S7DNlzs5W-mwj0fe1ZCDRFc9ws9XQE0SJE1jc2VKxhaLFIw9vEWSxW3yscwzkH1E3g-pPU-gOIt1aALZLEqkt_AsDUtxBoQv5uI2hCz9f2-jXVC9fP-GAjuKEjJtSU2GXaJsaDr4hOsG9JYoqf2WWwnp0_fVd0F5Wu5iaQiw7aveh3FGJ7N47AP0wXMBB2oiHrZofp173ttdAqyHKPQZ6B-Sfni8OS_YBUShaqfsZi_uzKlo77MwiXO3sbBnULAMs83K-rmXfTCSLtXAO6I8C-1tULJYa67D44eQaDKFAkpUfJXeyOeVmBwI4gUiVFGCVwa1tL19HAGFOW6F8L_8Ny2IA

Adding a non-folding region beforehand (like a newline) fixes this:

https://microsoft.github.io/monaco-editor/playground.html?source=v0.52.2#XQAAAAJ5AQAAAAAAAABBqQkHQ5NjdMjwa-jY7SIQ9S7DNlzs5W-mwj0fe1ZCDRFc9ws9XQE0SJE1jc2VKxhaLFIw9vEWSxW3yscwzhm7M3g-pPU-gOIt1aALZLEqkt_AsDUtxBoQv5uI2hCz9f2-jXVC9fP-GAjuKEjJtSU2GXaJsaDr4hOsG9JYKdgiy6gISMxFMX_IUt6WXKqvpCBaGP2xuAE5ELWqZxELAGPb3kqP_nCHeMih0Ttz33cqVL5wxLbVddzb8iISI7lNW9E1_8SrRwqcODuJ5MVn5m-L3qfuwQUtWPn4JAKMxtEL48hABSyi7_e9rCCEu_vHKSzx2pXwQLJgW8u325FY2grXzvH-8wHDOg

Monaco Editor Playground Code

var editor = monaco.editor.create(document.getElementById("container"), {
	value: `const hello = () => {
    // This does not collapse
	console.log("hello world");
}
const world = () => {
    // This collapses
	console.log("world, hello");
}`,
	language: "javascript"
});

editor.getAction('editor.foldLevel1').run();

Reproduction Steps

View the sandbox, all level 1 regions should be folded automatically.

Actual (Problematic) Behavior

All regions are folded apart from the first one if that region is on the first line

Expected Behavior

No response

Additional Context

No response

Start by running the Monaco Editor Playground reproduction from the linked v0.52.2 examples and inspect the editor.foldLevel1 action with the provided JavaScript sample. Confirm the first level-1 region is skipped while later regions fold, then verify that the corrected behavior folds every level-1 region, including one beginning on the first line.