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/components/file-pane.tsx

@@ -13,15 +13,12 @@ import { useTranslation } from "react-i18next";
 import { MarkdownRenderer } from "@/components/markdown/renderer";
 import { useIsCompactFormFactor } from "@/constants/layout";
 import { useSessionStore, type ExplorerFile } from "@/stores/session-store";
-import { useWebScrollViewScrollbar } from "@/components/use-web-scrollbar";
-import { useWebScrollbarStyle } from "@/hooks/use-web-scrollbar-style";
 import { highlightCode, type HighlightToken } from "@getpaseo/highlight";
 import { syntaxTokenStyleFor } from "@/styles/syntax-token-styles";
 import { inlineUnistylesStyle } from "@/styles/unistyles-inline-style";
 import { lineNumberGutterWidth } from "@/components/code-insets";
 import { CODE_SURFACE_DATASET } from "@/styles/code-surface";
 import { isRenderedMarkdownFile } from "@/components/file-pane-render-mode";
-import { isWeb } from "@/constants/platform";
 import type { AttachmentMetadata } from "@/attachments/types";
 import { useAttachmentPreviewUrl } from "@/attachments/use-attachment-preview-url";
 import { persistAttachmentFromBytes } from "@/attachments/service";
@@ -43,7 +40,6 @@ interface CodeLineProps {
 interface FilePreviewBodyProps {
   preview: ExplorerFile | null;
   isLoading: boolean;
-  showDesktopWebScrollbar: boolean;
   isMobile: boolean;
   location: WorkspaceFileLocation;
   imagePreviewUri: string | null;
@@ -192,7 +188,6 @@ const codeLineStyles = StyleSheet.create((theme) => ({
 function FilePreviewBody({
   preview,
   isLoading,
-  showDesktopWebScrollbar,
   isMobile,
   location,
   imagePreviewUri,
@@ -204,10 +199,6 @@ function FilePreviewBody({
     preview?.kind === "text" && isRenderedMarkdownFile(filePath) && !location.lineStart;
 
   const previewScrollRef = useRef<RNScrollView>(null);
-  const webScrollbarStyle = useWebScrollbarStyle();
-  const scrollbar = useWebScrollViewScrollbar(previewScrollRef, {
-    enabled: showDesktopWebScrollbar,
-  });
 
   const highlightedLines = useMemo(() => {
     if (!preview || preview.kind !== "text" || isMarkdownFile) {
@@ -276,15 +267,10 @@ function FilePreviewBody({
             ref={previewScrollRef}
             style={styles.previewContent}
             contentContainerStyle={styles.previewMarkdownScrollContent}
-            onLayout={scrollbar.onLayout}
-            onScroll={scrollbar.onScroll}
-            onContentSizeChange={scrollbar.onContentSizeChange}
-            scrollEventThrottle={16}
-            showsVerticalScrollIndicator={!showDesktopWebScrollbar}
+            showsVerticalScrollIndicator
           >
             <MarkdownRenderer text={preview.content ?? ""} />
           </RNScrollView>
-          {scrollbar.overlay}
         </View>
       );
     }
@@ -318,11 +304,7 @@ function FilePreviewBody({
         <RNScrollView
           ref={previewScrollRef}
           style={styles.previewContent}
-          onLayout={scrollbar.onLayout}
-          onScroll={scrollbar.onScroll}
-          onContentSizeChange={scrollbar.onContentSizeChange}
-          scrollEventThrottle={16}
-          showsVerticalScrollIndicator={!showDesktopWebScrollbar}
+          showsVerticalScrollIndicator
         >
           {isMobile ? (
             <View style={styles.previewCodeScrollContent}>{codeLines}</View>
@@ -331,14 +313,12 @@ function FilePreviewBody({
               horizontal
               nestedScrollEnabled
               showsHorizontalScrollIndicator
-              style={webScrollbarStyle}
               contentContainerStyle={styles.previewCodeScrollContent}
             >
               {codeLines}
             </RNScrollView>
           )}
         </RNScrollView>
-        {scrollbar.overlay}
       </View>
     );
   }
@@ -359,11 +339,7 @@ function FilePreviewBody({
           ref={previewScrollRef}
           style={styles.previewContent}
           contentContainerStyle={styles.previewImageScrollContent}
-          onLayout={scrollbar.onLayout}
-          onScroll={scrollbar.onScroll}
-          onContentSizeChange={scrollbar.onContentSizeChange}
-          scrollEventThrottle={16}
-          showsVerticalScrollIndicator={!showDesktopWebScrollbar}
+          showsVerticalScrollIndicator
         >
           <RNImage
             source={imageSource ?? undefined}
@@ -371,7 +347,6 @@ function FilePreviewBody({
             resizeMode="contain"
           />
         </RNScrollView>
-        {scrollbar.overlay}
       </View>
     );
   }
@@ -395,7 +370,6 @@ export function FilePane({
 }) {
   const { t } = useTranslation();
   const isMobile = useIsCompactFormFactor();
-  const showDesktopWebScrollbar = isWeb && !isMobile;
 
   const client = useSessionStore((state) => state.sessions[serverId]?.client ?? null);
   const normalizedWorkspaceRoot = useMemo(() => workspaceRoot.trim(), [workspaceRoot]);
@@ -463,7 +437,6 @@ export function FilePane({
       <FilePreviewBody
         preview={query.data?.file ?? null}
         isLoading={query.isFetching}
-        showDesktopWebScrollbar={showDesktopWebScrollbar}
         isMobile={isMobile}
         location={location}
         imagePreviewUri={imagePreviewUri}