fix: tool call bottom sheet text visibility

Replace react-native-gesture-handler ScrollView with React Native's
built-in ScrollView to fix text rendering issues inside @gorhom/bottom-sheet.
The gesture handler's ScrollView was causing text to render nearly invisible.

Also add explicit background colors to scroll containers for consistent
appearance.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

packages/app/src/components/tool-call-sheet.tsx

@@ -6,8 +6,7 @@ import React, {
   useRef,
   ReactNode,
 } from "react";
-import { View, Text, Pressable } from "react-native";
-import { ScrollView } from "react-native-gesture-handler";
+import { View, Text, Pressable, ScrollView } from "react-native";
 import { StyleSheet } from "react-native-unistyles";
 import {
   BottomSheetModal,
@@ -681,6 +680,7 @@ const styles = StyleSheet.create((theme) => ({
     borderColor: theme.colors.border,
     borderRadius: theme.borderRadius.base,
     maxHeight: 260,
+    backgroundColor: theme.colors.card,
   },
   scrollContent: {
     padding: theme.spacing[2],
@@ -695,6 +695,7 @@ const styles = StyleSheet.create((theme) => ({
     borderWidth: theme.borderWidth[1],
     borderColor: theme.colors.border,
     borderRadius: theme.borderRadius.base,
+    backgroundColor: theme.colors.card,
   },
   jsonScrollError: {
     borderColor: theme.colors.destructive,