feat(server): auto-fetch server metadata after validation

Server metadata is now automatically gathered when server validation completes successfully, both in the async job and Livewire component. This ensures server details (OS, CPU count, etc.) are populated immediately after validation passes, improving the user experience without requiring manual metadata fetching.

Tests added to verify gatherServerMetadata is called on successful validation and skipped when validation fails.

app/Jobs/ValidateAndInstallServerJob.php

@@ -179,6 +179,9 @@ class ValidateAndInstallServerJob implements ShouldBeEncrypted, ShouldQueue
             // Mark validation as complete
             $this->server->update(['is_validating' => false]);
 
+            // Auto-fetch server details now that validation passed
+            $this->server->gatherServerMetadata();
+
             // Refresh server to get latest state
             $this->server->refresh();