fix: Defensive factory cleanup on registration failure + VirtualEnv test

- Delete factory from map if SendAndWait fails, enabling retry with same name
- Add VirtualEnv test case to convertToProtoOptions coverage

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: wbreza

cli/azd/internal/grpcserver/external_provisioning_provider_test.go

@@ -89,6 +89,26 @@ func Test_convertToProtoOptions(t *testing.T) {
 				assert.Nil(t, result.Config)
 			},
 		},
+		{
+			name: "OptionsWithVirtualEnv",
+			options: provisioning.Options{
+				Provider: provisioning.Bicep,
+				Path:     "infra",
+				VirtualEnv: map[string]string{
+					"LAYER1_OUTPUT":   "value1",
+					"LAYER1_ENDPOINT": "https://example.com",
+				},
+			},
+			verify: func(t *testing.T, result *azdext.ProvisioningOptions, err error) {
+				require.NoError(t, err)
+				require.NotNil(t, result)
+				assert.Equal(t, "bicep", result.Provider)
+				assert.Equal(t, "infra", result.Path)
+				require.Len(t, result.VirtualEnv, 2)
+				assert.Equal(t, "value1", result.VirtualEnv["LAYER1_OUTPUT"])
+				assert.Equal(t, "https://example.com", result.VirtualEnv["LAYER1_ENDPOINT"])
+			},
+		},
 	}
 
 	for _, tt := range tests {

cli/azd/pkg/azdext/provisioning_manager.go

@@ -188,29 +188,39 @@ func (m *ProvisioningManager) Register(
 		},
 	}
 
+	// Store factory before RPC so the duplicate check works for concurrent calls.
+	m.mu.Lock()
+	m.factories[providerName] = factory
+	m.mu.Unlock()
+
 	resp, err := m.broker.SendAndWait(ctx, registerReq)
 	if err != nil {
+		// Clean up factory so the same name can be retried
+		m.mu.Lock()
+		delete(m.factories, providerName)
+		m.mu.Unlock()
 		return fmt.Errorf(
 			"provisioning provider registration failed: %w", err,
 		)
 	}
 
 	if resp == nil {
+		m.mu.Lock()
+		delete(m.factories, providerName)
+		m.mu.Unlock()
 		return fmt.Errorf("provisioning provider registration: received nil response")
 	}
 
 	if resp.GetRegisterProvisioningProviderResponse() == nil {
+		m.mu.Lock()
+		delete(m.factories, providerName)
+		m.mu.Unlock()
 		return fmt.Errorf(
 			"expected RegisterProvisioningProviderResponse, got %T",
 			resp.GetMessageType(),
 		)
 	}
 
-	// Store factory ONLY after successful registration
-	m.mu.Lock()
-	m.factories[providerName] = factory
-	m.mu.Unlock()
-
 	return nil
 }