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/git/actions-split-button.tsx

@@ -1,11 +1,6 @@
+import { LoadingSpinner } from "@/components/ui/loading-spinner";
 import { useCallback, useMemo } from "react";
-import {
-  View,
-  Text,
-  ActivityIndicator,
-  Pressable,
-  type PressableStateCallbackType,
-} from "react-native";
+import { View, Text, Pressable, type PressableStateCallbackType } from "react-native";
 import { StyleSheet, useUnistyles } from "react-native-unistyles";
 import { ChevronDown, Info, MoreVertical } from "lucide-react-native";
 import { useTranslation } from "react-i18next";
@@ -146,7 +141,7 @@ export function GitActionsSplitButton({ gitActions, hideLabels }: GitActionsSpli
             accessibilityLabel={gitActions.primary.label}
           >
             {gitActions.primary.status === "pending" ? (
-              <ActivityIndicator
+              <LoadingSpinner
                 size="small"
                 color={theme.colors.foreground}
                 style={styles.splitButtonSpinnerOnly}

packages/app/src/git/diff-pane.tsx

@@ -14,7 +14,6 @@ import { DiffStat } from "@/components/diff-stat";
 import {
   View,
   Text,
-  ActivityIndicator,
   Pressable,
   FlatList,
   type LayoutChangeEvent,
@@ -1320,7 +1319,7 @@ type PressableStyleFn = (
 
 const foregroundMutedIconColorMapping = (theme: Theme) => ({ color: theme.colors.foregroundMuted });
 
-const ThemedActivityIndicator = withUnistyles(ActivityIndicator);
+const ThemedLoadingSpinner = withUnistyles(LoadingSpinner);
 const ThemedAlignJustify = withUnistyles(AlignJustify);
 const ThemedColumns2 = withUnistyles(Columns2);
 const ThemedPilcrow = withUnistyles(Pilcrow);
@@ -1693,7 +1692,6 @@ export function DiffOptionsMenu({
 }
 
 const ThemedRotateCw = withUnistyles(RotateCw);
-const ThemedLoadingSpinner = withUnistyles(LoadingSpinner);
 
 type DiffFlatItemLayoutGetter = NonNullable<FlatListProps<DiffFlatItem>["getItemLayout"]>;
 const EMPTY_PATH_LIST: string[] = [];
@@ -1779,7 +1777,7 @@ function DiffBodyContent({
   if (isStatusLoading) {
     return (
       <View style={styles.loadingContainer}>
-        <ThemedActivityIndicator size="large" uniProps={foregroundMutedIconColorMapping} />
+        <ThemedLoadingSpinner size="large" uniProps={foregroundMutedIconColorMapping} />
         <Text style={styles.loadingText}>{checkingRepositoryLabel}</Text>
       </View>
     );
@@ -1801,7 +1799,7 @@ function DiffBodyContent({
   if (isDiffLoading) {
     return (
       <View style={styles.loadingContainer}>
-        <ThemedActivityIndicator size="large" uniProps={foregroundMutedIconColorMapping} />
+        <ThemedLoadingSpinner size="large" uniProps={foregroundMutedIconColorMapping} />
       </View>
     );
   }