Load complete chat history when reaching the top (#2481)

* fix(chat): load older timeline history consistently

Pagination depended on scroll events, so short or compacted initial pages could never request older history. Reevaluate edge visibility as layout and history change, and standardize loading indicators on the canonical app spinner.

* fix(chat): keep older history loading reliably

Use authoritative timeline cursor progress so merged rows cannot stall pagination. Wait for bottom anchoring before evaluating the history edge, and re-arm retries on a fresh upward gesture without automatic failure loops.

packages/app/src/components/message.tsx

@@ -1,9 +1,9 @@
+import { LoadingSpinner } from "@/components/ui/loading-spinner";
 import {
   View,
   Text,
   Image,
   Pressable,
-  ActivityIndicator,
   type GestureResponderEvent,
   type LayoutChangeEvent,
   StyleProp,
@@ -172,6 +172,7 @@ const ThemedTodoCheckIcon = withUnistyles(Check);
 const ThemedFileSymlinkIcon = withUnistyles(FileSymlink);
 const ThemedTriangleAlertIcon = withUnistyles(TriangleAlertIcon);
 const ThemedChevronRightIcon = withUnistyles(ChevronRight);
+const ThemedLoadingSpinner = withUnistyles(LoadingSpinner);
 
 const foregroundColorMapping = (theme: Theme) => ({ color: theme.colors.foreground });
 const foregroundMutedColorMapping = (theme: Theme) => ({
@@ -865,7 +866,9 @@ const AssistantMarkdownResolvedImage = memo(function AssistantMarkdownResolvedIm
     return (
       <View style={frameStyle}>
         <View style={stateSurfaceStyle}>
-          {loadState.status === "loading" ? <ActivityIndicator size="small" /> : null}
+          {loadState.status === "loading" ? (
+            <ThemedLoadingSpinner size="small" uniProps={foregroundMutedColorMapping} />
+          ) : null}
           {loadState.status === "error" ? (
             <Text style={assistantMessageStylesheet.imageErrorText}>
               {t("message.attachments.imageUnavailable")}
@@ -1004,7 +1007,7 @@ function AssistantMarkdownImage({
   if (query.isLoading || dataImageQuery.isLoading) {
     return (
       <View style={stateFrameStyle}>
-        <ActivityIndicator size="small" />
+        <ThemedLoadingSpinner size="small" uniProps={foregroundMutedColorMapping} />
       </View>
     );
   }
@@ -2244,7 +2247,7 @@ export const CompactionMarker = memo(function CompactionMarker({
       <View style={compactionStylesheet.line} />
       <View style={compactionStylesheet.label}>
         {status === "loading" ? (
-          <ActivityIndicator size="small" color="#a1a1aa" />
+          <LoadingSpinner size="small" color="#a1a1aa" />
         ) : (
           <Scissors size={12} color="#a1a1aa" />
         )}