refactor: remove performance monitoring and diagnostics infrastructure

packages/app/src/screens/agent/agent-ready-screen.tsx

@@ -30,11 +30,6 @@ import {
 import { useCreateFlowStore } from "@/stores/create-flow-store";
 import type { Agent } from "@/contexts/session-context";
 import type { StreamItem } from "@/types/stream";
-import {
-  buildAgentNavigationKey,
-  endNavigationTiming,
-} from "@/utils/navigation-timing";
-import { startPerfMonitor } from "@/utils/perf-monitor";
 import {
   checkoutStatusQueryKey,
   type CheckoutStatusPayload,
@@ -115,27 +110,6 @@ export function AgentReadyScreen({
   const lastConnectionError = runtimeSnapshot?.lastError ?? null;
   const isRuntimeSessionAvailable = Boolean(resolvedServerId && runtimeClient);
 
-  const focusServerId = resolvedServerId;
-  const navigationStatus = isRuntimeSessionAvailable
-    ? "ready"
-    : "session_unavailable";
-
-  useFocusEffect(
-    useCallback(() => {
-      if (!resolvedAgentId || !focusServerId) {
-        return;
-      }
-      const navigationKey = buildAgentNavigationKey(
-        focusServerId,
-        resolvedAgentId
-      );
-      endNavigationTiming(navigationKey, {
-        screen: "agent",
-        status: navigationStatus,
-      });
-    }, [focusServerId, navigationStatus, resolvedAgentId])
-  );
-
   if (!resolvedServerId || !runtimeClient) {
     return (
       <AgentSessionUnavailableState
@@ -294,15 +268,6 @@ function AgentScreenContent({
     }
     openFileExplorer();
   }, [activateExplorerTabForCheckout, openFileExplorer, resolveCurrentExplorerCheckout]);
-  useEffect(() => {
-    if (Platform.OS !== "web") {
-      return;
-    }
-    const scope = `agent:${serverId}:${agentId ?? "unknown"}`;
-    const stop = startPerfMonitor(scope);
-    return stop;
-  }, [serverId, agentId]);
-
   // Swipe-left gesture to open explorer sidebar on mobile
   const explorerOpenGesture = useExplorerOpenGesture({
     enabled: isMobile && mobileView === "agent",

packages/app/src/screens/open-project-screen.tsx

@@ -8,7 +8,7 @@ import { SidebarMenuToggle } from "@/components/headers/menu-header";
 import { useKeyboardShortcutsStore } from "@/stores/keyboard-shortcuts-store";
 import { usePanelStore } from "@/stores/panel-store";
 import { getIsTauriMac } from "@/constants/layout";
-import { useTrafficLightPadding } from "@/utils/tauri-window";
+import { useTauriDragHandlers, useTrafficLightPadding } from "@/utils/tauri-window";
 
 export function OpenProjectScreen({ serverId: _serverId }: { serverId: string }) {
   const { theme } = useUnistyles();
@@ -21,6 +21,7 @@ export function OpenProjectScreen({ serverId: _serverId }: { serverId: string })
   const isMobile = UnistylesRuntime.breakpoint === "xs" || UnistylesRuntime.breakpoint === "sm";
   const needsTrafficLightInset = !isMobile && !desktopAgentListOpen && getIsTauriMac();
   const trafficLightInset = needsTrafficLightInset ? trafficLightPadding.left : 0;
+  const dragHandlers = useTauriDragHandlers();
 
   useEffect(() => {
     if (!isMobile) {
@@ -29,7 +30,7 @@ export function OpenProjectScreen({ serverId: _serverId }: { serverId: string })
   }, [isMobile, openAgentList]);
 
   return (
-    <View style={styles.container}>
+    <View style={styles.container} {...dragHandlers}>
       <View style={[styles.menuToggle, { paddingTop: insets.top, paddingLeft: trafficLightInset }]}>
         <SidebarMenuToggle />
       </View>
@@ -56,6 +57,7 @@ const styles = StyleSheet.create((theme) => ({
   container: {
     flex: 1,
     backgroundColor: theme.colors.surface0,
+    userSelect: "none",
   },
   menuToggle: {
     position: "absolute",

packages/app/src/screens/workspace/workspace-draft-agent-tab.tsx

@@ -5,7 +5,6 @@ import { AgentInputArea } from '@/components/agent-input-area'
 import { FileDropZone } from '@/components/file-drop-zone'
 import { AgentStreamView } from '@/components/agent-stream-view'
 import type { ImageAttachment } from '@/components/message-input'
-import { MAX_CONTENT_WIDTH } from '@/constants/layout'
 import { useAgentFormState } from '@/hooks/use-agent-form-state'
 import { useDraftAgentCreateFlow } from '@/hooks/use-draft-agent-create-flow'
 import { useHostRuntimeSession } from '@/runtime/host-runtime'
@@ -260,8 +259,6 @@ const styles = StyleSheet.create((theme) => ({
   container: {
     flex: 1,
     width: '100%',
-    alignSelf: 'center',
-    maxWidth: MAX_CONTENT_WIDTH,
     backgroundColor: theme.colors.surface0,
   },
   contentContainer: {