update ui and other frontend updates

frontend/src/routes/join/[code]/+page.server.ts

@@ -0,0 +1,24 @@
+import { fail, redirect } from '@sveltejs/kit';
+import { joinMember, setDeviceTokenCookie } from '$lib/server/auth';
+
+export const actions = {
+	default: async (event) => {
+		const code = event.params.code;
+		const fd = await event.request.formData();
+		const name = fd.get('name') as string;
+
+		if (!name) {
+			return fail(400, { error: 'Name is required' });
+		}
+
+		const deviceToken = crypto.randomUUID();
+
+		try {
+			const result = await joinMember(code, name, deviceToken);
+			setDeviceTokenCookie(event, deviceToken);
+			throw redirect(303, `/${result.famSlug}/${result.name}`);
+		} catch (e) {
+			return fail(400, { error: e instanceof Error ? e.message : 'Invalid invite code' });
+		}
+	},
+};