Selection of multiple officials and role sub-categories

apps/api/prisma/schema.prisma

@@ -246,6 +246,7 @@ model User {
   ownedCompanies Company[]    @relation("CompanyOwner")
   ownedProjectCards ProjectCard[] @relation("ProjectCardOwner")
   activities     Activity[]   @relation("ActivityAssignee")
+  assignedActivities Activity[] @relation("ActivityAssignees")
   createdActivities Activity[] @relation("ActivityCreator")
   notes          Note[]       @relation("NoteAuthor")
   noteRevisions  NoteRevision[] @relation("NoteRevisionEditor")
@@ -288,6 +289,10 @@ model OrgRole {
   permissions    String[]     @default([])
   /// owner | admin | sales | support — نقش‌های سیستمی قابل حذف نیستند
   systemKey      String?
+  /// نقش والد برای سلسله‌مراتب زیرنقش‌ها
+  parentId       String?
+  parent         OrgRole?     @relation("OrgRoleTree", fields: [parentId], references: [id], onDelete: Restrict)
+  children       OrgRole[]    @relation("OrgRoleTree")
   users          User[]
   memberships    Membership[]
   createdAt      DateTime     @default(now())
@@ -295,6 +300,8 @@ model OrgRole {
 
   @@unique([organizationId, name])
   @@index([organizationId])
+  @@index([parentId])
+  @@index([organizationId, parentId])
 }
 
 model Membership {
@@ -579,6 +586,8 @@ model Activity {
   deal           Deal?          @relation(fields: [dealId], references: [id], onDelete: SetNull)
   assigneeId     String?
   assignee       User?          @relation("ActivityAssignee", fields: [assigneeId], references: [id], onDelete: SetNull)
+  /// مسئولان مشترک (علاوه بر assigneeId به‌عنوان مسئول اصلی)
+  assignees      User[]         @relation("ActivityAssignees")
   createdById    String?
   createdBy      User?          @relation("ActivityCreator", fields: [createdById], references: [id], onDelete: SetNull)
   notes          Note[]