feat: move or copy dialog with folder suggestions and a rule for what is already there

internal/agent/fs.go

@@ -80,6 +80,10 @@ func dispatchFS(env proto.TaskEnvelope) (any, error) {
 		var a proto.FSChmodArgs
 		_ = json.Unmarshal(env.Args, &a)
 		return fsChmod(a)
+	case proto.TaskFSCopy:
+		var a proto.FSCopyArgs
+		_ = json.Unmarshal(env.Args, &a)
+		return fsCopy(a)
 	default:
 		return nil, fmt.Errorf("неизвестная операция %q", env.Type)
 	}