fix(e2e): resolve SPA auth race conditions in Robot tests

- Rework Login As Admin: use sessionStorage flag + relative fetch login + polling loop
- Add data-testid to JailDetailPage error render path
- Add Collections library import for Get From List keyword
- Fix /jails API response extraction (returns {items, total} not plain list)
- Change Close Context to Close Browser for proper browser cleanup
- Add domcontentloaded + Sleep + polling to Config test to avoid premature timeout

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

frontend/src/pages/JailDetailPage.tsx

@@ -56,7 +56,7 @@ export function JailDetailPage(): React.JSX.Element {
 
   if (error) {
     return (
-      <div className={styles.root}>
+      <div className={styles.root} data-testid="jail-detail-page">
         <Link to="/jails" className={linkStyles.link}>
           <Button appearance="subtle" icon={<ArrowLeftRegular />}>
             Back to Jails
@@ -72,7 +72,7 @@ export function JailDetailPage(): React.JSX.Element {
   if (!jail) return <></>;
 
   return (
-    <div className={styles.root}>
+    <div className={styles.root} data-testid="jail-detail-page">
       <div className={styles.breadcrumb}>
         <Link to="/jails" className={linkStyles.link}>
           <Button appearance="subtle" size="small" icon={<ArrowLeftRegular />}>