fix: sidebar archived threads, split feed width, and split view archive actions

- Filter archived threads in buildThreadNavigationGroups so the sidebar
  matches the home list behavior
- Initialize viewportWidth to 0 in split layout to avoid oversized first
  render, and include viewportWidth in LegendList extraData for repaint
- Add long-press archive/delete actions to ThreadNavigationSidebar so
  thread management is available in split view

Author: cursoragent

apps/mobile/src/features/threads/ThreadFeed.tsx

@@ -1134,7 +1134,9 @@ export const ThreadFeed = memo(function ThreadFeed(props: ThreadFeedProps) {
   const initialScrollReadyRef = useRef(false);
   const lastContentHeightRef = useRef(0);
   const { width: windowWidth } = useWindowDimensions();
-  const [viewportWidth, setViewportWidth] = useState(windowWidth);
+  const [viewportWidth, setViewportWidth] = useState(() =>
+    props.layoutVariant === "split" ? 0 : windowWidth,
+  );
   const [interactionState, setInteractionState] = useState<{
     readonly copiedRowId: string | null;
     readonly expandedWorkGroups: Record<string, boolean>;
@@ -1206,6 +1208,7 @@ export const ThreadFeed = memo(function ThreadFeed(props: ThreadFeedProps) {
       markdownStyles,
       reviewCommentColors,
       userBubbleColor,
+      viewportWidth,
     }),
     [
       copiedRowId,
@@ -1215,6 +1218,7 @@ export const ThreadFeed = memo(function ThreadFeed(props: ThreadFeedProps) {
       markdownStyles,
       reviewCommentColors,
       userBubbleColor,
+      viewportWidth,
     ],
   );
   const presentedFeed = useMemo(

apps/mobile/src/features/threads/ThreadNavigationSidebar.tsx

@@ -1,7 +1,7 @@
 import type { EnvironmentThreadShell } from "@t3tools/client-runtime/state/shell";
 import { SymbolView } from "expo-symbols";
-import { useMemo, useState } from "react";
-import { Pressable, ScrollView, StyleSheet, TextInput, View } from "react-native";
+import { useCallback, useMemo, useState } from "react";
+import { Alert, Pressable, ScrollView, StyleSheet, TextInput, View } from "react-native";
 import { useSafeAreaInsets } from "react-native-safe-area-context";
 
 import { AppText as Text } from "../../components/AppText";
@@ -10,6 +10,7 @@ import { scopedThreadKey } from "../../lib/scopedEntities";
 import { relativeTime } from "../../lib/time";
 import { useThemeColor } from "../../lib/useThemeColor";
 import { useProjects, useThreadShells } from "../../state/entities";
+import { useThreadListActions } from "../home/useThreadListActions";
 import { buildThreadNavigationGroups } from "./thread-navigation-groups";
 import { threadStatusTone } from "./threadPresentation";
 
@@ -24,11 +25,23 @@ export function ThreadNavigationSidebar(props: {
   const projects = useProjects();
   const threads = useThreadShells();
   const [searchQuery, setSearchQuery] = useState("");
+  const { archiveThread, confirmDeleteThread } = useThreadListActions();
   const groups = useMemo(
     () => buildThreadNavigationGroups({ projects, threads, searchQuery }),
     [projects, searchQuery, threads],
   );
 
+  const handleThreadLongPress = useCallback(
+    (thread: EnvironmentThreadShell) => {
+      Alert.alert(thread.title, undefined, [
+        { text: "Cancel", style: "cancel" },
+        { text: "Archive", onPress: () => archiveThread(thread) },
+        { text: "Delete", style: "destructive", onPress: () => confirmDeleteThread(thread) },
+      ]);
+    },
+    [archiveThread, confirmDeleteThread],
+  );
+
   const backgroundColor = useThemeColor("--color-drawer");
   const borderColor = useThemeColor("--color-border");
   const foregroundColor = useThemeColor("--color-foreground");
@@ -131,6 +144,7 @@ export function ThreadNavigationSidebar(props: {
                       accessibilityLabel={thread.title}
                       accessibilityRole="button"
                       accessibilityState={{ selected }}
+                      onLongPress={() => handleThreadLongPress(thread)}
                       onPress={() => props.onSelectThread(thread)}
                       style={({ pressed }) => [
                         styles.threadRow,

apps/mobile/src/features/threads/thread-navigation-groups.ts

@@ -33,7 +33,9 @@ export function buildThreadNavigationGroups(input: {
 
   return groupProjectsByRepository(input).flatMap((group) => {
     const threads = Arr.sort(
-      group.projects.flatMap((projectGroup) => projectGroup.threads),
+      group.projects
+        .flatMap((projectGroup) => projectGroup.threads)
+        .filter((thread) => thread.archivedAt === null),
       threadActivityOrder,
     );
     const title = group.projects[0]?.project.title ?? group.title;