Wait for content the page owns before scanning it

Several accessibility scans ran against a page that had not finished
arriving, so axe reported violations the app does not have. The worst of
them was the medications case, which waited for a level-one heading and
then checked that a level-one heading exists. A page that really lost its
heading would have waited out the timeout under a misleading name instead
of failing the rule, which makes it a check that cannot fail rather than a
flaky one.

The filter rail was the other bad sentinel. It renders beside the loading
silhouettes rather than after them, so it was on screen while the rows were
still grey rectangles. Under an 8x CPU throttle the rail and the loading
marker resolved in the same 40ms poll and the rows a poll later.

Every case now gates on a marker the real component carries in its
resolved, non-empty branch, and on a component other than the one the scan
asserts. Both the desktop table and the mobile card list carry the same
marker so the wait holds at any viewport. No sentinel names a heading, the
app frame, a busy marker or the filter rail any more.

src/app/auth/login/page.tsx

@@ -363,7 +363,14 @@ export default function LoginPage() {
             />
           </div>
         ) : (
-          <div className="mt-8 space-y-4">
+          <div
+            // The login card's own action block. `<main>` around it belongs
+            // to the shell and is on screen before this page renders at all,
+            // so it is this marker, not the landmark, that says the form has
+            // arrived.
+            data-slot="login-actions"
+            className="mt-8 space-y-4"
+          >
             {oidcStatus?.enabled && (
               <Button
                 onClick={handleOidcLogin}

src/components/admin/app-log-preview-section.tsx

@@ -229,7 +229,13 @@ export function AppLogPreviewSection() {
                   </th>
                 </tr>
               </thead>
-              <tbody className="divide-border divide-y">
+              {/* `app-log-rows` names the read events. The branch above it
+                  is a spinner and the one below an empty state, so the
+                  marker exists only once the buffer has actually answered. */}
+              <tbody
+                data-slot="app-log-rows"
+                className="divide-border divide-y"
+              >
                 {events.map((event, i) => {
                   const actionLabel =
                     event.action?.name ??

src/components/admin/backups-section.tsx

@@ -658,7 +658,12 @@ export function BackupsSection() {
                   </th>
                 </tr>
               </thead>
-              <tbody className="divide-border divide-y">
+              {/* `backup-rows` names the read rows. The three branches above
+                  are a spinner, a load error and an empty state, so the
+                  marker cannot stand for a page that has not answered yet.
+                  The narrow-layout list below carries it too, so a wait on
+                  it holds at any viewport. */}
+              <tbody data-slot="backup-rows" className="divide-border divide-y">
                 {rows.map((row, i) => (
                   <tr key={row.id} className={i % 2 === 0 ? "bg-muted/30" : ""}>
                     <td className="px-3 py-2 font-medium">{row.username}</td>
@@ -713,6 +718,7 @@ export function BackupsSection() {
               stay reachable on a phone instead of scrolling off-screen. */}
           <ul
             className="space-y-2 md:hidden"
+            data-slot="backup-rows"
             data-testid="admin-backups-mobile-list"
           >
             {rows.map((row) => (

src/components/admin/recent-audit-preview.tsx

@@ -99,7 +99,10 @@ export function RecentAuditPreview() {
             title={t("admin.overview.auditEmpty")}
           />
         ) : (
-          <ul className="divide-border divide-y">
+          // `admin-audit-rows` names the read entries. The branches above
+          // are a spinner, a load error and an empty state, so the marker
+          // stands for a card that has actually answered.
+          <ul data-slot="admin-audit-rows" className="divide-border divide-y">
             {entries.map((entry) => {
               const isFailed = entry.action === "auth.login.failed";
               // F-31 (v1.4.19): each row links into the full

src/components/admin/system-status-section.tsx

@@ -141,7 +141,13 @@ export function SystemStatusSection() {
           description={t("admin.systemStatusDescription")}
         />
         {status ? (
-          <div className="mt-4 grid gap-4 pl-7 sm:grid-cols-2 lg:grid-cols-4">
+          <div
+            // `system-status-grid` names the answered snapshot. The two
+            // branches below it are a load error and a spinner, so the
+            // marker cannot stand for a section still waiting on the read.
+            data-slot="system-status-grid"
+            className="mt-4 grid gap-4 pl-7 sm:grid-cols-2 lg:grid-cols-4"
+          >
             <StatusItem
               icon={Database}
               label={t("admin.database")}

src/components/admin/user-management-section.tsx

@@ -354,7 +354,15 @@ export function UserManagementSection() {
                     </th>
                   </tr>
                 </thead>
-                <tbody className="divide-border divide-y">
+                {/* `admin-user-rows` names the read accounts. The section
+                    renders an empty state instead when the list is empty and
+                    nothing at all while the query is in flight, so the marker
+                    stands for answered data. The mobile card list below
+                    carries it too, so a wait on it holds at any viewport. */}
+                <tbody
+                  data-slot="admin-user-rows"
+                  className="divide-border divide-y"
+                >
                   {filteredUsers.map((u, i) => (
                     <tr key={u.id} className={i % 2 === 0 ? "bg-muted/30" : ""}>
                       <td className="px-3 py-2 font-medium">{u.username}</td>
@@ -392,6 +400,7 @@ export function UserManagementSection() {
               is hidden behind a horizontal scroll. */}
             <ul
               className="mt-4 space-y-2 md:hidden"
+              data-slot="admin-user-rows"
               data-testid="admin-users-mobile-list"
             >
               {filteredUsers.map((u) => (

src/components/labs/lab-list.tsx

@@ -184,7 +184,10 @@ export function LabList({ onAddFirst }: { onAddFirst?: () => void } = {}) {
   // (#40); the card/tile view is the alternative the settings toggle selects.
   if (prefs.view === "list") {
     return (
-      <div className="space-y-3">
+      // `lab-list` marks the read results in both view shapes. The loading
+      // branch above carries `lab-list-loading` instead, so the marker
+      // cannot stand for a silhouette.
+      <div data-slot="lab-list" className="space-y-3">
         {truncated ? (
           <p className="text-muted-foreground text-xs">
             {t("labs.showingLatestOf", { shown, total })}
@@ -259,6 +262,7 @@ export function LabList({ onAddFirst }: { onAddFirst?: () => void } = {}) {
   // control on the tile; the trash icon lives only on the value detail view.
   return (
     <ul
+      data-slot="lab-list"
       className={cn(
         "grid list-none gap-4 p-0",
         // A lone lab spans the full row rather than orphaning half of it;

src/components/measurements/measurement-list.tsx

@@ -964,7 +964,16 @@ export function MeasurementList({
           <>
             {/* Desktop table — rendered only when not mobile (v1.28.42 H3). */}
             {!isMobile && (
-              <div className="bg-card border-border hidden overflow-hidden rounded-lg border md:block">
+              <div
+                // `measurement-rows` marks the READ rows, not the list frame:
+                // the filter rail above renders next to the loading
+                // silhouettes as well, so it proves nothing about the data
+                // having arrived. This wrapper exists only in the resolved,
+                // non-empty branch, and the mobile list below carries the
+                // same marker so a wait on it holds at any viewport.
+                data-slot="measurement-rows"
+                className="bg-card border-border hidden overflow-hidden rounded-lg border md:block"
+              >
                 <Table>
                   <TableHeader>
                     <TableRow>
@@ -1216,7 +1225,7 @@ export function MeasurementList({
 
             {/* Mobile list — rendered only when mobile (v1.28.42 H3). */}
             {isMobile && (
-              <div className="space-y-2 md:hidden">
+              <div data-slot="measurement-rows" className="space-y-2 md:hidden">
                 {data.measurements.map((m) => {
                   const Icon = TYPE_ICONS[m.type];
                   const isGrouped =

src/components/mood/mood-list.tsx

@@ -629,7 +629,16 @@ export function MoodList({ onAddFirst }: MoodListProps = {}) {
         ) : (
           <>
             {/* Desktop table */}
-            <div className="bg-card border-border hidden overflow-hidden rounded-lg border md:block">
+            <div
+              // `mood-rows` marks the READ entries, not the list frame: the
+              // filter rail above renders next to the loading silhouettes
+              // too, so it proves nothing about the data having arrived.
+              // This wrapper exists only in the resolved, non-empty branch,
+              // and the mobile list below carries the same marker so a wait
+              // on it holds at any viewport.
+              data-slot="mood-rows"
+              className="bg-card border-border hidden overflow-hidden rounded-lg border md:block"
+            >
               <Table>
                 <TableHeader>
                   <TableRow>
@@ -760,7 +769,7 @@ export function MoodList({ onAddFirst }: MoodListProps = {}) {
                 `data-testid="mood-row"` hook is what the Playwright Pixel-5
                 guard at `e2e/mood-card-mobile.spec.ts` queries to assert
                 "exactly one occurrence of the score per row". */}
-            <div className="space-y-2 md:hidden">
+            <div data-slot="mood-rows" className="space-y-2 md:hidden">
               {data.entries.map((entry) => {
                 const isSelected = selectedIds.has(entry.id);
                 return (