Prevent Android chats from freezing or going blank (#1989)

* fix(app): stabilize streamed chat rendering

Use deterministic Markdown AST keys and preserve unique row identities when an assistant message resumes after a tool. Keep native gesture and plan-card children correctly keyed to avoid unsupported Fabric reconciliation paths.

* fix(app): stabilize retained native panels

Keep retained workspace roots in a stable native order and make active
panels present in the selection commit. Hidden panels now stop expensive
subscriptions and animations without losing mounted state.

* fix(app): harden retained panel activity

packages/app/src/agent-stream/turn-footer.tsx

@@ -35,18 +35,23 @@ export type AssistantTurnForkHandler = (input: {
 
 export const TurnFooter = memo(function TurnFooter({
   isRunning,
+  isActive,
   inFlightTurnStartedAt,
   host,
   strategy,
   onForkAssistantTurn,
 }: {
   isRunning: boolean;
+  isActive: boolean;
   inFlightTurnStartedAt: Date | null;
   host: TurnFooterHost | null;
   strategy: TurnContentStrategy;
   onForkAssistantTurn?: AssistantTurnForkHandler;
 }) {
   if (isRunning) {
+    if (!isActive) {
+      return null;
+    }
     return (
       <TurnFooterRow>
         <RunningTurnFooter inFlightTurnStartedAt={inFlightTurnStartedAt} />

packages/app/src/agent-stream/view.tsx

@@ -2,7 +2,6 @@ import React, {
   forwardRef,
   memo,
   useCallback,
-  useContext,
   useEffect,
   useImperativeHandle,
   useMemo,
@@ -88,7 +87,7 @@ import { useStableEvent } from "@/hooks/use-stable-event";
 import { isWeb } from "@/constants/platform";
 import type { Theme } from "@/styles/theme";
 import { recordRenderProfileReasons } from "@/utils/render-profiler";
-import { MountedTabActiveContext } from "@/components/split-container";
+import { useRetainedPanelActive } from "@/components/retained-panel";
 import { generateDraftId } from "@/stores/draft-keys";
 import {
   buildDraftWorkspaceAttachmentScopeKey,
@@ -509,7 +508,7 @@ const AgentStreamViewComponent = forwardRef<AgentStreamViewHandle, AgentStreamVi
     // cell-window renders on every 48ms flush from background agents.
     // When isActive flips back to true, the context change triggers a re-render and
     // the component reads the current (fresh) streamItems/streamHead from props.
-    const isActive = useContext(MountedTabActiveContext);
+    const isActive = useRetainedPanelActive();
     const frozenStreamItemsRef = useRef(streamItems);
     const frozenStreamHeadRef = useRef(streamHead);
     if (isActive) {
@@ -773,6 +772,7 @@ const AgentStreamViewComponent = forwardRef<AgentStreamViewHandle, AgentStreamVi
         showRunningTurnFooter || bottomTurnFooterHost ? (
           <TurnFooter
             isRunning={showRunningTurnFooter}
+            isActive={isActive}
             inFlightTurnStartedAt={baseRenderModel.turnTiming.runningStartedAt}
             host={bottomTurnFooterHost}
             strategy={streamRenderStrategy}
@@ -781,6 +781,7 @@ const AgentStreamViewComponent = forwardRef<AgentStreamViewHandle, AgentStreamVi
         ) : null,
       [
         handleForkAssistantTurn,
+        isActive,
         showRunningTurnFooter,
         baseRenderModel.turnTiming.runningStartedAt,
         bottomTurnFooterHost,