feat: onboarding trial flow, Google sign-in, dark mode hotspot fixes

- Move trial creation from auth hook to dedicated /subscriptions/trial endpoint
  with eligibility checks (3-day Full Paket trial)
- Add animated onboarding progress (Remotion) with confetti on completion
- Register redirects to subscription page with welcome flow
- Add Google social login/signup support with config injection
- Improve hotspot overlay visibility in dark mode
- Show "Panele Git" on landing page when authenticated
- Turkish translations for API error messages
- Add toast utility wrapper, UUID generation for auth IDs

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/web/src/routes/__root.tsx

@@ -1,5 +1,5 @@
 import { createRootRouteWithContext, Outlet } from "@tanstack/react-router";
-import { Toaster } from "sonner";
+import { Toaster } from "@/lib/toast";
 import type { QueryClient } from "@tanstack/react-query";
 import { useEffect } from "react";
 import { getUserSettings } from "@/lib/user-settings";
@@ -36,7 +36,7 @@ function RootComponent() {
   return (
     <>
       <Outlet />
-      <Toaster position="top-right" richColors />
+      <Toaster position="top-center" />
     </>
   );
 }