feat(market): add Minha Intenções tab with panel, hook, and badge

- Introduced "Minhas Intenções" tab visible only to logged-in users.
- Integrated MyPurchaseIntentionsPanel and useMyPurchaseIntentions hook.
- Added tab badge showing count of pending intentions.
- Extended session API to include user’s main character for downstream features.

components/chat/ChatModal.tsx

@@ -0,0 +1,147 @@
+"use client";
+
+import { useState, useEffect } from "react";
+import {
+  Dialog,
+  DialogContent,
+  DialogDescription,
+  DialogHeader,
+  DialogTitle,
+} from "@/components/ui/dialog";
+import { ChatHeader } from "./ChatHeader";
+import { MessageList } from "./MessageList";
+import { MessageInput } from "./MessageInput";
+import { useChat } from "@/lib/hooks/use-chat";
+import { useSession } from "@/lib/hooks/use-session";
+import { Skeleton } from "@/components/ui/skeleton";
+
+interface ChatModalProps {
+  open: boolean;
+  onOpenChange: (open: boolean) => void;
+  listingId?: number | null;
+  chatId?: string | null;
+  initialMessage?: string;
+}
+
+export function ChatModal({
+  open,
+  onOpenChange,
+  listingId,
+  chatId: initialChatId,
+  initialMessage,
+}: ChatModalProps) {
+  const { user } = useSession();
+  const [chatId, setChatId] = useState<string | null>(initialChatId || null);
+  const [isCreatingChat, setIsCreatingChat] = useState(false);
+
+  const {
+    chat,
+    messages,
+    isLoading,
+    isSending,
+    sendMessage,
+    loadMoreMessages,
+    hasMore,
+    otherUserTyping,
+  } = useChat(chatId);
+
+  // Se chatId for fornecido diretamente, usar ele
+  useEffect(() => {
+    if (initialChatId) {
+      setChatId(initialChatId);
+      return;
+    }
+  }, [initialChatId]);
+
+  // Criar ou buscar chat quando modal abrir (apenas se não tiver chatId)
+  useEffect(() => {
+    if (!open || !user || !listingId || initialChatId) {
+      if (!initialChatId && !listingId) {
+        setChatId(null);
+      }
+      return;
+    }
+
+    const createOrGetChat = async () => {
+      setIsCreatingChat(true);
+      try {
+        const res = await fetch("/api/chats", {
+          method: "POST",
+          headers: {
+            "Content-Type": "application/json",
+          },
+          credentials: "include",
+          body: JSON.stringify({
+            listing_id: listingId,
+            buyer_message: initialMessage,
+          }),
+        });
+
+        if (!res.ok) {
+          throw new Error("Erro ao criar chat");
+        }
+
+        const data = await res.json();
+        setChatId(data.chat.chat_id);
+
+        // Se houver mensagem inicial, já foi enviada no backend
+      } catch (error) {
+        console.error("Erro ao criar/buscar chat:", error);
+      } finally {
+        setIsCreatingChat(false);
+      }
+    };
+
+    createOrGetChat();
+  }, [open, user, listingId, initialMessage, initialChatId]);
+
+  if (!user) {
+    return null;
+  }
+
+  return (
+    <Dialog open={open} onOpenChange={onOpenChange}>
+      <DialogContent className="max-w-2xl h-[80vh] flex flex-col p-0 gap-0">
+        <DialogHeader className="sr-only">
+          <DialogTitle>Chat com vendedor</DialogTitle>
+          <DialogDescription>
+            Conversa sobre o anúncio
+          </DialogDescription>
+        </DialogHeader>
+
+        {isCreatingChat || (isLoading && !chat) ? (
+          <div className="flex-1 flex items-center justify-center">
+            <div className="space-y-4 w-full px-4">
+              <Skeleton className="h-24 w-full" />
+              <Skeleton className="h-64 w-full" />
+              <Skeleton className="h-20 w-full" />
+            </div>
+          </div>
+        ) : chat ? (
+          <>
+            <ChatHeader chat={chat} currentUserId={user.userId} />
+            <MessageList
+              messages={messages}
+              currentUserId={user.userId}
+              isLoading={isLoading}
+              onLoadMore={loadMoreMessages}
+              hasMore={hasMore}
+              otherUserTyping={otherUserTyping}
+            />
+            <MessageInput
+              onSend={sendMessage}
+              isSending={isSending}
+              disabled={!chat.is_active}
+              chatId={chatId}
+            />
+          </>
+        ) : (
+          <div className="flex-1 flex items-center justify-center text-center text-muted-foreground">
+            <p>Erro ao carregar chat</p>
+          </div>
+        )}
+      </DialogContent>
+    </Dialog>
+  );
+}
+