[Bug] Duplicate underlines in model makers with `code` that has a `target`

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

https://microsoft.github.io/monaco-editor/playground.html?source=v0.54.0-dev-20250916#XQAAAAK-BQAAAAAAAABBqQkHQ5NjdMjwa-jY7SIQ9S7DNlzs5W-mwj0fe1ZCDRFc9ws9XQE0SJE1jc2VKxhaLFIw9vEWSxW3yscw9ehbjwLINgRABDcFm89fBOSueOLTYt0aaEwnsLoPwmLxwedOn8Q8TDA7HdG2A53dB9AMwMH_c2UsEDCPbL8A4cD4wMZ1VB0MWs_y8RU4Rfp30mb6j4qTZKwUsJT_Y6UO5T9OwHKk44-wuN3FrNkoMlyuHr9pGHVtjhrklmGHrcy0-LqP9muYZYtszV0OOFI0KwyofOIRcJI_i_VGlYJIkUONR11xqsXKDvLnjkjwTRvpUtCs08KlP136Xme_NvlziGY2yv0QATuwfy55XkdSpy1JsupnWflFj-DieEjMAsQp5m7Bxec4rFWdqcmwcgyRSXOotE5SSBMvHby5WUohzPzZrPP09gS-2FImOIlKy3Mu_zbWcY5tZ2641TZejtPKCgiX5ILxEFO8H6G9onmZHbeT_d1YqnPIXeSLTrpOYyBMhh0sBd8wiAoLnEDQoxO6Ft1X6M-OiBUvX5vgYXJibFLcZyIQXwVPc854TCja1fOcO4j6SsGZ9AqmasBANLAM87Ba39m9Spf-299BS9vch6olcpfmIPfbHnku2SkkTghKW50qpzw2GsLo34CcK86IFl_2Fg6pvdui82XNq9M8-3xXF6aMTQIeFUjiWIsd0gX4mhhA6UJry4SN-hr-xuh34GaTwTbvaWJJ4XRpHE-gOtcdAKh52bShRw20bc73L8Ka-gXmicGa_0OzVrE67t7X7w2rq8xOlUpF9H7cRFmzg5rb2OWSJ6C0y2XuvfcVVlmP_0nAl8wOTzUBC475oI3ibEec39HSY5JIRRyX9R_69vrW

Monaco Editor Playground Code

function validate(model) {
	const markers = [];
	// lines start at 1
	for (let i = 1; i < model.getLineCount() + 1; i++) {
		const range = {
			startLineNumber: i,
			startColumn: 1,
			endLineNumber: i,
			endColumn: model.getLineLength(i) + 1,
		};
		const content = model.getValueInRange(range).trim();
		const number = Number(content);
		if (Number.isNaN(number)) {
			markers.push({
				message: "not a number",
				severity: monaco.MarkerSeverity.Error,
				startLineNumber: range.startLineNumber,
				startColumn: range.startColumn,
				endLineNumber: range.endLineNumber,
				endColumn: range.endColumn,
				code: {
					value: 'NAN',
					target: monaco.Uri.parse('https://example.com/')
				}
			});
		} else if (!Number.isInteger(number)) {
			markers.push({
				message: "not an integer",
				severity: monaco.MarkerSeverity.Warning,
				startLineNumber: range.startLineNumber,
				startColumn: range.startColumn,
				endLineNumber: range.endLineNumber,
				endColumn: range.endColumn,
			});
		}
	}
	monaco.editor.setModelMarkers(model, "owner", markers);
}

const value = `12345
abcd
234.56
12345
abcd
234.56`;
const uri = monaco.Uri.parse("inmemory://test");
const model = monaco.editor.createModel(value, "demoLanguage", uri);
const editor = monaco.editor.create(document.getElementById("container"), {
	model,
});
validate(model);
model.onDidChangeContent(() => {
	validate(model);
});

Reproduction Steps

Hover on the abcd to see hover contents

Actual (Problematic) Behavior

Duplicate underlines.

Expected Behavior

Only one underline, the same as vscode.

Additional Context

No response