Restructure UX and seed a fully simulated organisation

Rework the dashboard, environment topology view, header navigation, and
status rendering, and standardise selects on a shadcn-vue component.

Replace the thin database seeder with a SimulatedEnvironmentSeeder that
builds a fully wired, mostly-running organisation (ACTIVE server fleet,
managed + GHCR registries, Gitea source provider, ClipBin app with
production/staging environments, services, slices, endpoints, managed
variables, build artifacts, and a completed/in-progress/failed operations
history) so the new UI renders against realistic data.

app/Http/Middleware/HandleInertiaRequests.php

@@ -30,11 +30,7 @@ class HandleInertiaRequests extends Middleware
         return [
             ...parent::share($request),
             'name' => config('app.name'),
-            'organisation' => $request->route('organisation')
-                ? Organisation::with('applications.environments')
-                    ->withCount(['providers', 'sourceProviders', 'registries', 'servers', 'applications'])
-                    ->findOrFail($this->routeKey($request->route('organisation')))
-                : null,
+            'organisation' => $this->resolveOrganisation($request),
             'application' => $request->route('application')
                 ? Application::with('environments')->findOrFail($this->routeKey($request->route('application')))
                 : null,
@@ -53,6 +49,20 @@ class HandleInertiaRequests extends Middleware
         ];
     }
 
+    private function resolveOrganisation(Request $request): ?Organisation
+    {
+        $query = Organisation::with('applications.environments')
+            ->withCount(['providers', 'sourceProviders', 'registries', 'servers', 'applications']);
+
+        if ($request->route('organisation')) {
+            return $query->findOrFail($this->routeKey($request->route('organisation')));
+        }
+
+        $organisationId = $request->user()?->organisations()->value('organisations.id');
+
+        return $organisationId ? $query->find($organisationId) : null;
+    }
+
     private function routeKey(mixed $routeValue): mixed
     {
         return $routeValue instanceof Model ? $routeValue->getKey() : $routeValue;