Implement remote current-state discovery for the restore subcommand

internal/app/restore.go

@@ -11,6 +11,9 @@ import (
 	"gitea.maximumdirect.net/eric/narratio/internal/config"
 )
 
+var newObjectStoreFromConfigFn = storage.NewObjectStoreFromConfig
+var discoverRemoteCurrentStateFn = discoverRemoteCurrentState
+
 // Restore validates restore CLI/config inputs and storage preflight for future restore phases.
 func Restore(ctx context.Context, args []string, out io.Writer) error {
 	fs := flag.NewFlagSet("restore", flag.ContinueOnError)
@@ -63,14 +66,23 @@ func Restore(ctx context.Context, args []string, out io.Writer) error {
 		return fmt.Errorf("restore: %w", err)
 	}
 
-	_, err = storage.NewObjectStoreFromConfig(ctx, cfg)
+	objectStore, err := newObjectStoreFromConfigFn(ctx, cfg)
+	if err != nil {
+		return fmt.Errorf("restore: %w", err)
+	}
+	current, err := discoverRemoteCurrentStateFn(ctx, cfg, objectStore)
 	if err != nil {
 		return fmt.Errorf("restore: %w", err)
 	}
 
-	// Phase 2 boundary: command wiring and preflight only.
+	// Phase 3 boundary: discovery is implemented; planning/execution is deferred.
 	_ = dryRun
 	_ = force
 	_ = includeAudio
-	return fmt.Errorf("restore: not yet implemented (phase 3: remote current-state discovery)")
+	return fmt.Errorf(
+		"restore: discovered remote current state for %s/%s (run %s); not yet implemented (phase 3: remote current-state discovery)",
+		current.Campaign,
+		current.SessionID,
+		current.RunID,
+	)
 }