feat: implement QuestionBank CRUD with pagination and template query

- Add pagination support to findAll (page, limit query params)
- Add findByTemplateId method to service
- Add GET /by-template/:templateId endpoint to controller
- Service already includes CRUD for QuestionBank and QuestionBankItem

server/src/assessment/entities/question-bank-item.entity.ts

@@ -0,0 +1,104 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  ManyToOne,
+  JoinColumn,
+} from 'typeorm';
+import { QuestionBank } from './question-bank.entity';
+
+export enum QuestionBankItemStatus {
+  PENDING_REVIEW = 'PENDING_REVIEW',
+  PUBLISHED = 'PUBLISHED',
+}
+
+export enum QuestionType {
+  SHORT_ANSWER = 'SHORT_ANSWER',
+  MULTIPLE_CHOICE = 'MULTIPLE_CHOICE',
+  TRUE_FALSE = 'TRUE_FALSE',
+}
+
+export enum QuestionDifficulty {
+  STANDARD = 'STANDARD',
+  ADVANCED = 'ADVANCED',
+  SPECIALIST = 'SPECIALIST',
+}
+
+export enum QuestionDimension {
+  PROMPT = 'PROMPT',
+  LLM = 'LLM',
+  IDE = 'IDE',
+  DEV_PATTERN = 'DEV_PATTERN',
+  WORK_CAPABILITY = 'WORK_CAPABILITY',
+}
+
+@Entity('question_bank_items')
+export class QuestionBankItem {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ name: 'bank_id' })
+  bankId: string;
+
+  @ManyToOne(
+    () => QuestionBank,
+    (bank: QuestionBank) => bank.items,
+    { onDelete: 'CASCADE' },
+  )
+  @JoinColumn({ name: 'bank_id' })
+  bank: QuestionBank;
+
+  @Column({ type: 'text', name: 'question_text' })
+  questionText: string;
+
+  @Column({
+    type: 'enum',
+    enum: QuestionType,
+    default: QuestionType.SHORT_ANSWER,
+  })
+  questionType: QuestionType;
+
+  @Column({ type: 'simple-json', nullable: true })
+  options: string[] | null;
+
+  @Column({ type: 'text', nullable: true })
+  correctAnswer: string | null;
+
+  @Column({ type: 'simple-json', name: 'key_points' })
+  keyPoints: string[];
+
+  @Column({
+    type: 'enum',
+    enum: QuestionDifficulty,
+    default: QuestionDifficulty.STANDARD,
+  })
+  difficulty: QuestionDifficulty;
+
+  @Column({
+    type: 'enum',
+    enum: QuestionDimension,
+    default: QuestionDimension.PROMPT,
+  })
+  dimension: QuestionDimension;
+
+  @Column({ type: 'text', nullable: true })
+  basis: string | null;
+
+  @Column({ name: 'created_by', nullable: true })
+  createdBy: string | null;
+
+  @Column({
+    type: 'enum',
+    enum: QuestionBankItemStatus,
+    default: QuestionBankItemStatus.PENDING_REVIEW,
+  })
+  status: QuestionBankItemStatus;
+
+  @CreateDateColumn({ name: 'created_at' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at' })
+  updatedAt: Date;
+}