Extend database with more tables, rewrite API doc, improve API endpoints

software/backend/models/accountRole.model.ts

@@ -0,0 +1,19 @@
+import { Column, HasMany, Model, Table } from "sequelize-typescript";
+import { Account } from "./account.model";
+
+@Table({ timestamps: false })
+export class AccountRole extends Model {
+  @Column
+  name: string
+
+  @Column
+  privilegeBuy: boolean
+
+  @Column
+  privilegeAdminPanel: boolean
+
+
+  // Relations
+  @HasMany(() => Account)
+  accounts: Account[]
+}