- Reworked the tenant admin login page

- Updated the User model to implement Filament’s tenancy contracts
- Seeded a ready-to-use demo tenant (user, tenant, active package, purchase)
- Introduced a branded, translated 403 error page to replace the generic forbidden message for unauthorised admin hits
- Removed the public “Register” links from the marketing header
- hardened join event logic and improved error handling in the guest pwa.

public/manifest.json

@@ -0,0 +1,43 @@
+{
+  "name": "Fotospiel Tenant Admin",
+  "short_name": "Fotospiel Admin",
+  "id": "/event-admin",
+  "start_url": "/event-admin/",
+  "scope": "/event-admin/",
+  "display": "standalone",
+  "lang": "de-DE",
+  "description": "Verwalte Events, Pakete und Gäste mobil – inklusive geführtem Onboarding und schnellen Management-Tools.",
+  "background_color": "#0f172a",
+  "theme_color": "#f43f5e",
+  "orientation": "portrait",
+  "categories": ["productivity", "photo-video"],
+  "icons": [
+    {
+      "src": "/favicon.svg",
+      "sizes": "any",
+      "type": "image/svg+xml",
+      "purpose": "any"
+    },
+    {
+      "src": "/apple-touch-icon.png",
+      "sizes": "180x180",
+      "type": "image/png",
+      "purpose": "any"
+    }
+  ],
+  "shortcuts": [
+    {
+      "name": "Neues Event planen",
+      "short_name": "Event planen",
+      "url": "/event-admin/welcome",
+      "description": "Starte den geführten Onboarding-Prozess für dein nächstes Event."
+    },
+    {
+      "name": "Dashboard",
+      "short_name": "Dashboard",
+      "url": "/event-admin/",
+      "description": "Direkt zur Übersicht deiner Events und Aufgaben."
+    }
+  ],
+  "prefer_related_applications": false
+}