fix(a11y): use role="status" for the Vertex credentials path warning

role="alert" implies aria-live="assertive" by default, which mixed
awkwardly with the explicit aria-live="polite" override (urgent role
+ don't-interrupt liveness). For an informational warning that fires
as the user types into a settings field, role="status" is the
conventional pattern — implicitly polite, semantically correct for a
non-urgent dynamic message, and removes the role/live conflict.

Author: 0xMink

webview-ui/src/components/settings/providers/Vertex.tsx

@@ -94,8 +94,7 @@ export const Vertex = ({ apiConfiguration, setApiConfigurationField }: VertexPro
 			{credentialsLooksLikePath && (
 				<div
 					data-testid="vertex-credentials-path-warning"
-					role="alert"
-					aria-live="polite"
+					role="status"
 					className="text-sm text-vscode-errorForeground">
 					<Trans
 						i18nKey="settings:providers.googleCloudCredentialsPathWarning"