feat: implement chat page with conversation list, message view, and polling

src/components/ConversationList.tsx

@@ -0,0 +1,47 @@
+import { useState, useEffect } from "react";
+import { invoke } from "@tauri-apps/api/core";
+
+interface Conversation {
+  id: string;
+  name: string | null;
+  kind: string;
+}
+
+interface Props {
+  workspaceId: string;
+  onSelect: (id: string) => void;
+  selectedId: string | null;
+}
+
+export default function ConversationList({ workspaceId, onSelect, selectedId }: Props) {
+  const [conversations, setConversations] = useState<Conversation[]>([]);
+  const [error, setError] = useState<string | null>(null);
+
+  useEffect(() => {
+    invoke<Conversation[]>("list_conversations", { workspaceId })
+      .then(setConversations)
+      .catch((e) => setError(String(e)));
+  }, [workspaceId]);
+
+  return (
+    <div style={{ width: 220, borderRight: "1px solid #ccc", overflowY: "auto" }}>
+      <div style={{ padding: "12px 16px", fontWeight: "bold", borderBottom: "1px solid #ccc" }}>
+        Conversations
+      </div>
+      {error && <p style={{ color: "red", padding: 8 }}>{error}</p>}
+      {conversations.map((c) => (
+        <div
+          key={c.id}
+          onClick={() => onSelect(c.id)}
+          style={{
+            padding: "10px 16px",
+            cursor: "pointer",
+            background: selectedId === c.id ? "#e8f0fe" : "transparent",
+          }}
+        >
+          {c.name ?? `(${c.kind})`}
+        </div>
+      ))}
+    </div>
+  );
+}

src/components/MessageInput.tsx

@@ -0,0 +1,31 @@
+import { useState } from "react";
+import { invoke } from "@tauri-apps/api/core";
+
+export default function MessageInput({ conversationId }: { conversationId: string }) {
+  const [content, setContent] = useState("");
+  const [error, setError] = useState<string | null>(null);
+
+  async function handleSend() {
+    if (!content.trim()) return;
+    try {
+      await invoke("send_message", { conversationId, content });
+      setContent("");
+      setError(null);
+    } catch (e) {
+      setError(String(e));
+    }
+  }
+
+  return (
+    <div style={{ padding: 16, borderTop: "1px solid #ccc" }}>
+      {error && <p style={{ color: "red", margin: "0 0 8px" }}>{error}</p>}
+      <input
+        value={content}
+        onChange={(e) => setContent(e.target.value)}
+        onKeyDown={(e) => e.key === "Enter" && handleSend()}
+        placeholder="Type a message and press Enter…"
+        style={{ width: "100%", padding: 10, boxSizing: "border-box", fontSize: 14 }}
+      />
+    </div>
+  );
+}

src/components/MessageList.tsx

@@ -0,0 +1,46 @@
+import { useState, useEffect, useRef } from "react";
+import { invoke } from "@tauri-apps/api/core";
+
+interface Message {
+  id: string;
+  user_id: string;
+  content: string;
+  created_at: string;
+}
+
+export default function MessageList({ conversationId }: { conversationId: string }) {
+  const [messages, setMessages] = useState<Message[]>([]);
+  const [error, setError] = useState<string | null>(null);
+  const bottomRef = useRef<HTMLDivElement>(null);
+
+  useEffect(() => {
+    const load = () =>
+      invoke<Message[]>("list_messages", { conversationId })
+        .then((msgs) => {
+          setMessages(msgs);
+          bottomRef.current?.scrollIntoView({ behavior: "smooth" });
+        })
+        .catch((e) => setError(String(e)));
+
+    load();
+    // ponytail: polling every 3s — replace with WebSocket when server supports it
+    const id = setInterval(load, 3000);
+    return () => clearInterval(id);
+  }, [conversationId]);
+
+  return (
+    <div style={{ flex: 1, overflowY: "auto", padding: 16 }}>
+      {error && <p style={{ color: "red" }}>{error}</p>}
+      {messages.map((m) => (
+        <div key={m.id} style={{ marginBottom: 12 }}>
+          <strong style={{ marginRight: 8 }}>{m.user_id}</strong>
+          <span style={{ color: "#888", fontSize: 12, marginRight: 8 }}>
+            {new Date(m.created_at).toLocaleTimeString()}
+          </span>
+          <div>{m.content}</div>
+        </div>
+      ))}
+      <div ref={bottomRef} />
+    </div>
+  );
+}

src/pages/ChatPage.tsx

@@ -1,3 +1,32 @@
+import { useState } from "react";
+import { useParams } from "react-router-dom";
+import ConversationList from "../components/ConversationList";
+import MessageList from "../components/MessageList";
+import MessageInput from "../components/MessageInput";
+
 export default function ChatPage() {
-  return <div>Chat</div>;
+  const { workspaceId } = useParams<{ workspaceId: string }>();
+  const [conversationId, setConversationId] = useState<string | null>(null);
+
+  return (
+    <div style={{ display: "flex", height: "100vh" }}>
+      <ConversationList
+        workspaceId={workspaceId!}
+        onSelect={setConversationId}
+        selectedId={conversationId}
+      />
+      <div style={{ flex: 1, display: "flex", flexDirection: "column" }}>
+        {conversationId ? (
+          <>
+            <MessageList conversationId={conversationId} />
+            <MessageInput conversationId={conversationId} />
+          </>
+        ) : (
+          <div style={{ flex: 1, display: "flex", alignItems: "center", justifyContent: "center", color: "#888" }}>
+            Select a conversation
+          </div>
+        )}
+      </div>
+    </div>
+  );
 }