Refine tool call summaries and scrolling (#2069)

* feat(app): refine tool call summaries and scrolling

Keep summary groups stable from the first tool call, preserve live activity feedback, and scroll expanded groups to the latest entry. Consolidate web scrollbar styling around the native browser mechanism.

* refactor(app): reuse tool call height constant

* fix(app): preserve tool call summary state

* fix(app): refresh web tool groups on expand

* fix(app): preserve grouped tool errors

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

@@ -85,7 +85,6 @@ import {
 import { Tooltip, TooltipTrigger, TooltipContent } from "@/components/ui/tooltip";
 import { GitHubIcon } from "@/components/icons/github-icon";
 import { lineNumberGutterWidth } from "@/components/code-insets";
-import { useWebScrollViewScrollbar } from "@/components/use-web-scrollbar";
 import { GitActionsSplitButton } from "@/git/actions-split-button";
 import { BranchSwitcher } from "@/components/branch-switcher";
 import { useGitActions } from "@/git/use-actions";
@@ -1536,8 +1535,6 @@ interface DiffBodyContentProps {
   diffListRef: RefObject<FlatList<DiffFlatItem> | null>;
   handleDiffListLayout: (event: LayoutChangeEvent) => void;
   handleDiffListScroll: (event: NativeSyntheticEvent<NativeScrollEvent>) => void;
-  onContentSizeChange: (width: number, height: number) => void;
-  showDesktopWebScrollbar: boolean;
   checkingRepositoryLabel: string;
   notRepositoryLabel: string;
 }
@@ -1559,8 +1556,6 @@ function DiffBodyContent({
   diffListRef,
   handleDiffListLayout,
   handleDiffListScroll,
-  onContentSizeChange,
-  showDesktopWebScrollbar,
   checkingRepositoryLabel,
   notRepositoryLabel,
 }: DiffBodyContentProps) {
@@ -1621,9 +1616,8 @@ function DiffBodyContent({
       testID="git-diff-scroll"
       onLayout={handleDiffListLayout}
       onScroll={handleDiffListScroll}
-      onContentSizeChange={onContentSizeChange}
       scrollEventThrottle={16}
-      showsVerticalScrollIndicator={!showDesktopWebScrollbar}
+      showsVerticalScrollIndicator
       // Mixed-height rows (header + potentially very large body) are prone to clipping artifacts.
       // Keep a larger render window and disable clipping to avoid bodies disappearing mid-scroll.
       removeClippedSubviews={false}
@@ -1737,7 +1731,6 @@ export function GitDiffPane({ serverId, workspaceId, cwd, enabled }: GitDiffPane
   const { settings: appSettings } = useAppSettings();
   const { t } = useTranslation();
   const isMobile = useIsCompactFormFactor();
-  const showDesktopWebScrollbar = isWeb && !isMobile;
   const canUseSplitLayout = isWeb && !isMobile;
   const { preferences: changesPreferences, updatePreferences: updateChangesPreferences } =
     useChangesPreferences();
@@ -1963,9 +1956,6 @@ export function GitDiffPane({ serverId, workspaceId, cwd, enabled }: GitDiffPane
     }
     void updateChangesPreferences({ viewMode: nextViewMode });
   }, [setDiffCollapsedFoldersForWorkspace, updateChangesPreferences, viewMode, workspaceStateKey]);
-  const scrollbar = useWebScrollViewScrollbar(diffListRef, {
-    enabled: showDesktopWebScrollbar,
-  });
   const diffListScrollOffsetRef = useRef(0);
   const diffListViewportHeightRef = useRef(0);
   const headerHeightByPathRef = useRef<Record<string, number>>({});
@@ -2089,25 +2079,17 @@ export function GitDiffPane({ serverId, workspaceId, cwd, enabled }: GitDiffPane
     [getBodyHeightKey],
   );
 
-  const handleDiffListScroll = useCallback(
-    (event: NativeSyntheticEvent<NativeScrollEvent>) => {
-      diffListScrollOffsetRef.current = event.nativeEvent.contentOffset.y;
-      scrollbar.onScroll(event);
-    },
-    [scrollbar],
-  );
+  const handleDiffListScroll = useCallback((event: NativeSyntheticEvent<NativeScrollEvent>) => {
+    diffListScrollOffsetRef.current = event.nativeEvent.contentOffset.y;
+  }, []);
 
-  const handleDiffListLayout = useCallback(
-    (event: LayoutChangeEvent) => {
-      const height = event.nativeEvent.layout.height;
-      if (!Number.isFinite(height) || height <= 0) {
-        return;
-      }
-      diffListViewportHeightRef.current = height;
-      scrollbar.onLayout(event);
-    },
-    [scrollbar],
-  );
+  const handleDiffListLayout = useCallback((event: LayoutChangeEvent) => {
+    const height = event.nativeEvent.layout.height;
+    if (!Number.isFinite(height) || height <= 0) {
+      return;
+    }
+    diffListViewportHeightRef.current = height;
+  }, []);
 
   // Offset of the first item matching `predicate`, walking the SAME flatItems
   // list getFlatItemLayout uses so folder rows are counted (single source of
@@ -2379,8 +2361,6 @@ export function GitDiffPane({ serverId, workspaceId, cwd, enabled }: GitDiffPane
       diffListRef={diffListRef}
       handleDiffListLayout={handleDiffListLayout}
       handleDiffListScroll={handleDiffListScroll}
-      onContentSizeChange={scrollbar.onContentSizeChange}
-      showDesktopWebScrollbar={showDesktopWebScrollbar}
       checkingRepositoryLabel={t("workspace.git.diff.checkingRepository")}
       notRepositoryLabel={t("workspace.git.diff.notRepository")}
     />
@@ -2479,10 +2459,7 @@ export function GitDiffPane({ serverId, workspaceId, cwd, enabled }: GitDiffPane
 
       {prErrorMessage ? <Text style={styles.actionErrorText}>{prErrorMessage}</Text> : null}
 
-      <View style={styles.diffContainer}>
-        {bodyContent}
-        {hasChanges ? scrollbar.overlay : null}
-      </View>
+      <View style={styles.diffContainer}>{bodyContent}</View>
     </View>
   );
 }