Implement MongoDB-based storage for Pack Run approval, artifact, log, and state management

- Added MongoPackRunApprovalStore for managing approval states with MongoDB.
- Introduced MongoPackRunArtifactUploader for uploading and storing artifacts.
- Created MongoPackRunLogStore to handle logging of pack run events.
- Developed MongoPackRunStateStore for persisting and retrieving pack run states.
- Implemented unit tests for MongoDB stores to ensure correct functionality.
- Added MongoTaskRunnerTestContext for setting up MongoDB test environment.
- Enhanced PackRunStateFactory to correctly initialize state with gate reasons.

src/__Libraries/StellaOps.Cryptography.Kms/GcpKmsFacade.cs

@@ -51,7 +51,7 @@ internal sealed class GcpKmsFacade : IGcpKmsFacade
         var builder = new KeyManagementServiceClientBuilder
         {
             Endpoint = string.IsNullOrWhiteSpace(options.Endpoint)
-                ? KeyManagementServiceClient.DefaultEndpoint.Host
+                ? KeyManagementServiceClient.DefaultEndpoint
                 : options.Endpoint,
         };
 
@@ -149,9 +149,9 @@ internal sealed class GcpKmsFacade : IGcpKmsFacade
 
     public void Dispose()
     {
-        if (_ownsClient)
+        if (_ownsClient && _client is IDisposable disposable)
         {
-            _client.Dispose();
+            disposable.Dispose();
         }
     }