Add a guided setup after signup, and a no-model notice in conversations

The first super admin now lands on Settings > Setup after signing up: a
skippable walk through the app name, connecting a model provider and
picking models, ending with where to go next. It stays under Settings to
come back to.

While a bot has no text model, its conversation shows a notice in the
thread (centred when empty): super admins get Connect a provider and
Guided setup, everyone else is told the super admin sets it up. The
models modal keeps it current.

The Models page's data and save logic move into useModelsOverview, shared
with the setup.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/pages/admin/bots/[bot_id]/(sections)/conversation.tsx

@@ -39,6 +39,7 @@ import useConversationHistory from "../(hooks)/use-conversation-history";
 import mergeLoadedHistory from "../(utils)/merge-loaded-history";
 import LoadingLine from "@/src/components/general/loading-line";
 import SessionMovedBar from "../(partials)/session-moved-bar";
+import NoModelNotice from "../(partials)/no-model-notice";
 import syncSessionQuery from "../(utils)/sync-session-query";
 import announceShownSession from "@/src/functions/frontend/announce-shown-session";
 
@@ -85,6 +86,11 @@ export default function Conversation() {
      */
     const [moved_to_session_id, setMovedToSessionId] = useState<number | null>(null);
     const [has_other_unread, setHasOtherUnread] = useState(false);
+    /**
+     * The text model the bot runs on here; none shows a notice in the
+     * thread. A save in the models modal updates it.
+     */
+    const [text_model, setTextModel] = useState(pageProps?.bot_text_model || null);
     const [reply_to, setReplyTo] = useState<BotMessageWithAttachments | null>(
         null,
     );
@@ -391,6 +397,8 @@ export default function Conversation() {
                                     bot={live_bot}
                                     workspace={workspace}
                                     has_other_unread={has_other_unread}
+                                    model={text_model}
+                                    onModelChange={setTextModel}
                                 />
                                 {history.loading ? (
                                     <LoadingLine label="Loading the conversation" />
@@ -409,6 +417,11 @@ export default function Conversation() {
                                     receiving={pending_messages.length > 0}
                                     has_task={Boolean(progress.task_id)}
                                     moved_on={Boolean(moved_to_session_id)}
+                                    notice={
+                                        !text_model && !history.loading ? (
+                                            <NoModelNotice bot_name={live_bot.name || "This bot"} />
+                                        ) : null
+                                    }
                                     older={older}
                                     onQuote={({ text }) =>
                                         composer.current?.insertQuote({ text })