perf(mobile): show cached child content first and drop sibling prefetch

apps/mobile/src/components/agents/child-session-message.test.ts

@@ -239,8 +239,8 @@ describe('ChildSessionMessage routing seam', () => {
   });
 });
 
-describe('ChildSessionSection model label', () => {
-  it('renders the model label when child messages carry model data', () => {
+describe('ChildSessionSection card metadata', () => {
+  it('does not render a transcript-derived model label on the card', () => {
     const childMessages = [makeMessage([makeTextPart('child text')])];
     const onOpenChildSession = vi.fn<(sessionId: string, title: string) => void>();
     const part = makeToolPart('task', taskCompletedState);
@@ -253,23 +253,6 @@ describe('ChildSessionSection model label', () => {
       onOpenChildSession,
     });
 
-    const labels = findByType(root, ChildSessionModelLabel);
-    expect(labels).toHaveLength(1);
-    expect(labels[0]?.props).toMatchObject({ modelLabel: 'Test Model' });
-  });
-
-  it('hides the model label when child messages are empty and still renders the card', () => {
-    const onOpenChildSession = vi.fn<(sessionId: string, title: string) => void>();
-    const part = makeToolPart('task', taskCompletedState);
-
-    // eslint-disable-next-line new-cap, react-compiler-runtime/react-compiler-runtime -- direct function call
-    const root = ChildSessionSection({
-      part,
-      childMessages: [],
-      modelOptions: [modelOption],
-      onOpenChildSession,
-    });
-
     expect(findByType(root, ChildSessionModelLabel)).toHaveLength(0);
     const taskNameTexts = findAll(
       root,

apps/mobile/src/components/agents/child-session-section.tsx

@@ -22,8 +22,6 @@ import {
   getChildSessionCardState,
   getTaskToolSessionId,
 } from './child-session-card-state';
-import { getChildSessionModelLabel } from './child-session-model';
-import { ChildSessionModelLabel } from './child-session-model-label';
 import { MessageErrorBoundary } from './message-error-boundary';
 import { isToolPart } from './part-types';
 
@@ -55,16 +53,12 @@ type ChildSessionSectionProps = {
 
 export function ChildSessionSection({
   part,
-  childMessages,
   onOpenChildSession,
-  modelOptions,
 }: Readonly<ChildSessionSectionProps>) {
   const colors = useThemeColors();
   const { t } = useTranslation();
 
   const { agentName, taskName, status }: ChildSessionCardState = getChildSessionCardState(part);
-  const modelLabel =
-    childMessages.length > 0 ? getChildSessionModelLabel(childMessages, modelOptions ?? []) : null;
 
   const isRunning = status === 'running' || status === 'pending';
   const sessionId = getTaskToolSessionId(part);
@@ -90,7 +84,6 @@ export function ChildSessionSection({
         accessibilityLabel={t('agentChat.childSession.accessibilityLabel', {
           agentName,
           taskName,
-          modelLabel: modelLabel ? `, ${modelLabel}` : '',
           status: t(CHILD_SESSION_STATUS_LABEL_KEYS[status]),
         })}
         accessibilityHint={sessionId ? t('agentChat.childSession.openHint') : undefined}
@@ -111,7 +104,6 @@ export function ChildSessionSection({
           <Text className="text-sm leading-5 text-foreground" numberOfLines={1}>
             {taskName}
           </Text>
-          {modelLabel ? <ChildSessionModelLabel modelLabel={modelLabel} /> : null}
         </View>
 
         <StatusBadge status={status} />

apps/mobile/src/i18n/locales/en.json

@@ -2475,7 +2475,7 @@
       "waitingForPermission": "The agent is waiting for permission. While this request is open, your message to the agent is paused."
     },
     "childSession": {
-      "accessibilityLabel": "{{agentName}}, {{taskName}}{{modelLabel}}, {{status}}",
+      "accessibilityLabel": "{{agentName}}, {{taskName}}, {{status}}",
       "maxNestingDepth": "Maximum nesting depth reached.",
       "modelAccessibility": "Model: {{modelLabel}}",
       "openHint": "Open subagent session",