Add duplicate and clear submissions functionality for challenge chains; implement corresponding dialogs and API endpoints, enhancing user experience and task management. Update localization for new features in English and Russian.

src/types/challenge.ts

@@ -142,6 +142,16 @@ export interface UpdateChainRequest {
   isActive?: boolean
 }
 
+export interface DuplicateChainRequest {
+  name?: string
+}
+
+export interface ClearSubmissionsResponse {
+  deletedCount: number
+  chainId: string
+  userId?: string
+}
+
 // ========== Stats v2 Types ==========
 
 export type TaskProgressStatus = 'not_started' | 'pending' | 'in_progress' | 'needs_revision' | 'completed'