fix: guard identification factor selection

Signed-off-by: Vitor Mattos <1079143+vitormattos@users.noreply.github.com>

Author: vitormattos

src/views/Settings/IdentificationFactors.vue

@@ -97,18 +97,19 @@ function updateSignatureMethodsEnabled() {
 		if (!Object.hasOwn(identifyMethod, 'signatureMethodEnabled')) {
 			identifyMethod.signatureMethodEnabled = ''
 		}
+		const currentSelection = identifyMethod.signatureMethodEnabled ?? ''
 
-		if (identifyMethod.signatureMethodEnabled.length === 0) {
+		if (currentSelection.length === 0) {
 			const selectedSignatureMethod = signatureMethodNames
 				.reduce((currentSelection, signatureMethodName) => {
 					const signatureMethod = identifyMethod.signatureMethods[signatureMethodName]
 					if (currentSelection.length === 0 && signatureMethod?.enabled) {
 						return signatureMethodName
 					}
 					return currentSelection
-				}, identifyMethod.signatureMethodEnabled)
+				}, currentSelection)
 
-			identifyMethod.signatureMethodEnabled = selectedSignatureMethod.length > 0
+			identifyMethod.signatureMethodEnabled = (selectedSignatureMethod ?? '').length > 0
 				? selectedSignatureMethod
 				: (signatureMethodNames[0] ?? '')
 		}