fix: goal+language in ChannelEdit, metrics 500 (await params)

ChannelEdit.js:
- Добавлены goal (multi-select + кастомные, как в форме создания)
- Добавлен language (select: ru/en/uk/kk)
- Импортированы Plus, X иконки и GOALS константа

app/api/metrics/channel/[channelId]/route.js:
app/api/metrics/best-time/[channelId]/route.js:
- await params (Next.js 16 требует), иначе 500

app/api/metrics/channel/[channelId]/route.js

@@ -7,7 +7,8 @@ export async function GET(request, { params }) {
   if (!user) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
   const { searchParams } = new URL(request.url);
   try {
-    const data = await engine.getChannelMetrics(params.channelId, Object.fromEntries(searchParams));
+    const { channelId } = await params;
+    const data = await engine.getChannelMetrics(channelId, Object.fromEntries(searchParams));
     return NextResponse.json(data);
   } catch (err) {
     return NextResponse.json({ error: err.message }, { status: err.status || 500 });