fix(order): stabilize zustand selector snapshots

Move filter-based derivations out of Zustand selectors in order/chat/review detail pages so snapshots stay stable under useSyncExternalStore checks. Add evidence-backed comments referencing React useSyncExternalStore guidance and Zustand issues #1936/#3155 to document the regression trigger.

app/(order)/chat/[id]/page.tsx

@@ -3,7 +3,7 @@
 import { ArrowLeft, ImagePlus, Lock, Send } from "lucide-react"
 import Image from "next/image"
 import Link from "next/link"
-import { use, useRef, useState } from "react"
+import { use, useMemo, useRef, useState } from "react"
 import { Avatar, AvatarFallback, AvatarImage } from "@/components/ui/avatar"
 import { Badge } from "@/components/ui/badge"
 import { Button } from "@/components/ui/button"
@@ -16,7 +16,15 @@ import { useChatStore } from "@/store/chat"
 export default function ChatDetailPage({ params }: { params: Promise<{ id: string }> }) {
   const { id } = use(params)
   const session = useChatStore((state) => state.sessions.find((item) => item.id === id))
-  const messages = useChatStore((state) => state.messages.filter((item) => item.sessionId === id))
+  const allMessages = useChatStore((state) => state.messages)
+  // Filter logic runs here via useMemo rather than inside the Zustand selector.
+  // useSyncExternalStore requires a stable snapshot reference on each render.
+  // Inline filter in a selector creates a new array per call and can trigger
+  // infinite re-render loops in Zustand v5 (pmndrs/zustand#1936).
+  const messages = useMemo(
+    () => allMessages.filter((item) => item.sessionId === id),
+    [allMessages, id],
+  )
   const sendTextMessage = useChatStore((state) => state.sendTextMessage)
   const sendImageMessage = useChatStore((state) => state.sendImageMessage)
   const [input, setInput] = useState("")