Add /config endpoint integration with lazy loading

Implements client-side integration for the new /config API endpoint
that allows backplane-cli to fetch server-managed configuration values.

Features:
- Refresh command: 'ocm backplane config refresh' to force update server values
- Backwards compatible: Existing config files work without changes

Implementation:
- New ConfigAPIClient interface for fetching remote config
- New refresh command to manually update server-managed values

Server-managed values:
- jira-base-url
- assume-initial-arn
- prod-env-name
- jira-config-for-access-requests

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: smarthall

cmd/ocm-backplane/config/config.go

@@ -32,5 +32,6 @@ govcloud    Set to true if used in FedRAMP
 	cmd.AddCommand(newGetCmd())
 	cmd.AddCommand(newSetCmd())
 	cmd.AddCommand(newTroubleshootCmd())
+	cmd.AddCommand(newRefreshCmd())
 	return cmd
 }

cmd/ocm-backplane/config/refresh.go

@@ -0,0 +1,129 @@
+package config
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+
+	BackplaneApi "github.com/openshift/backplane-api/pkg/client"
+	"github.com/openshift/backplane-cli/pkg/cli/config"
+	"github.com/openshift/backplane-cli/pkg/info"
+	"github.com/openshift/backplane-cli/pkg/ocm"
+	logger "github.com/sirupsen/logrus"
+)
+
+func newRefreshCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "refresh",
+		Short: "Refresh configuration from backplane-api server",
+		Long: `Fetch the latest configuration values from the backplane-api server and update the local config file.
+
+This command will overwrite the following server-managed configuration values:
+  - jira-base-url
+  - assume-initial-arn
+  - prod-env-name
+  - jira-config-for-access-requests
+
+User-defined values (proxy-url, session-dir, etc.) will not be modified.`,
+		SilenceUsage: true,
+		Args:         cobra.NoArgs,
+		RunE:         runRefresh,
+	}
+
+	return cmd
+}
+
+func runRefresh(cmd *cobra.Command, args []string) error {
+	logger.Info("Refreshing configuration from backplane-api...")
+
+	// Get current config to determine backplane URL
+	bpConfig, err := config.GetBackplaneConfiguration()
+	if err != nil {
+		return fmt.Errorf("failed to load current configuration: %w", err)
+	}
+
+	// Get OCM access token
+	token, err := ocm.DefaultOCMInterface.GetOCMAccessToken()
+	if err != nil {
+		return fmt.Errorf("failed to get OCM access token: %w", err)
+	}
+
+	// Create backplane API client
+	client, err := BackplaneApi.NewClient(bpConfig.URL, func(c *BackplaneApi.Client) error {
+		c.RequestEditors = append(c.RequestEditors, func(ctx context.Context, req *http.Request) error {
+			req.Header.Add("Authorization", "Bearer "+*token)
+			req.Header.Set("User-Agent", "backplane-cli"+info.Version)
+			req.Header.Set("Backplane-Version", info.DefaultInfoService.GetVersion())
+			return nil
+		})
+		return nil
+	})
+	if err != nil {
+		return fmt.Errorf("failed to create backplane API client: %w", err)
+	}
+
+	// Fetch fresh config from API
+	remoteConfig, err := config.DefaultAPIClient.FetchRemoteConfig(client)
+	if err != nil {
+		return fmt.Errorf("failed to fetch configuration from server: %w", err)
+	}
+
+	// Get config file path
+	configPath, err := config.GetConfigFilePath()
+	if err != nil {
+		return fmt.Errorf("failed to get config file path: %w", err)
+	}
+
+	// Reset viper to clear any defaults that were set by GetBackplaneConfiguration
+	// This prevents defaults like 'govcloud' from leaking into the user's config file
+	viper.Reset()
+
+	// Load existing config file to preserve user settings
+	viper.SetConfigFile(configPath)
+	viper.SetConfigType("json")
+	if err := viper.ReadInConfig(); err != nil {
+		// If config doesn't exist, that's okay - we'll create it
+		logger.Debugf("No existing config file found, will create new one")
+	}
+
+	// Update only server-managed values
+	updated := false
+	if remoteConfig.JiraBaseURL != nil {
+		viper.Set(config.JiraBaseURLKey, *remoteConfig.JiraBaseURL)
+		logger.Infof("Updated jira-base-url: %s", *remoteConfig.JiraBaseURL)
+		updated = true
+	}
+
+	if remoteConfig.AssumeInitialArn != nil {
+		viper.Set(config.AssumeInitialArnKey, *remoteConfig.AssumeInitialArn)
+		logger.Infof("Updated assume-initial-arn: %s", *remoteConfig.AssumeInitialArn)
+		updated = true
+	}
+
+	if remoteConfig.ProdEnvName != nil {
+		viper.Set(config.ProdEnvNameKey, *remoteConfig.ProdEnvName)
+		logger.Infof("Updated prod-env-name: %s", *remoteConfig.ProdEnvName)
+		updated = true
+	}
+
+	if remoteConfig.JiraConfigForAccessRequests != nil {
+		viper.Set(config.JiraConfigForAccessRequestsKey, remoteConfig.JiraConfigForAccessRequests)
+		logger.Info("Updated jira-config-for-access-requests")
+		updated = true
+	}
+
+	if !updated {
+		logger.Warn("No configuration values were returned from the server")
+	}
+
+	// Write updated config to file
+	if err := viper.WriteConfigAs(configPath); err != nil {
+		return fmt.Errorf("failed to write config file: %w", err)
+	}
+
+	fmt.Printf("Configuration refreshed successfully and saved to %s\n", configPath)
+	return nil
+}