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/globals.css

@@ -77,6 +77,19 @@
 }
 .animate-fade-in-up { animation: fade-in-up 0.3s ease-out; }
 
+/* Sileo toast: deeper state colors for light mode */
+:root {
+  --sileo-state-success: oklch(0.52 0.24 142);
+  --sileo-state-error: oklch(0.48 0.26 25);
+  --sileo-state-warning: oklch(0.58 0.2 70);
+  --sileo-state-info: oklch(0.50 0.2 237);
+  --sileo-state-loading: oklch(0.40 0 0);
+}
+
+[data-sileo-description] {
+  color: #333;
+}
+
 .dark {
   --color-background: #0a0a0a;
   --color-foreground: #fafafa;
@@ -100,4 +113,20 @@
   --color-card-foreground: #fafafa;
   --color-popover: #0a0a0a;
   --color-popover-foreground: #fafafa;
+
+  /* Sileo toast: dark pill/body, light text, subtler shadow */
+  --sileo-state-loading: oklch(0.7 0 0);
+}
+
+.dark [data-sileo-pill],
+.dark [data-sileo-body] {
+  fill: #1c1c1e !important;
+}
+
+.dark [data-sileo-description] {
+  color: #d4d4d4;
+}
+
+.dark [data-sileo-toast] {
+  filter: drop-shadow(0 0 12px rgba(0, 0, 0, 0.4));
 }