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/services/template.service.ts

@@ -0,0 +1,89 @@
+import {
+  Injectable,
+  NotFoundException,
+  ForbiddenException,
+} from '@nestjs/common';
+import { InjectRepository } from '@nestjs/typeorm';
+import { Repository } from 'typeorm';
+import { AssessmentTemplate } from '../entities/assessment-template.entity';
+import { CreateTemplateDto } from '../dto/create-template.dto';
+import { UpdateTemplateDto } from '../dto/update-template.dto';
+import { TenantService } from '../../tenant/tenant.service';
+
+@Injectable()
+export class TemplateService {
+  constructor(
+    @InjectRepository(AssessmentTemplate)
+    private readonly templateRepository: Repository<AssessmentTemplate>,
+    private readonly tenantService: TenantService,
+  ) {}
+
+  async create(
+    createDto: CreateTemplateDto,
+    userId: string,
+    tenantId: string,
+  ): Promise<AssessmentTemplate> {
+    const { ...data } = createDto;
+    const template = this.templateRepository.create({
+      ...data,
+      createdBy: userId,
+      tenantId,
+    });
+    return this.templateRepository.save(template);
+  }
+
+  async findAll(tenantId: string): Promise<AssessmentTemplate[]> {
+    return this.templateRepository.find({
+      where: { tenantId, isActive: true },
+      relations: ['knowledgeGroup'],
+      order: { createdAt: 'DESC' },
+    });
+  }
+
+  async findOne(
+    id: string,
+    userId: string,
+    tenantId: string,
+  ): Promise<AssessmentTemplate> {
+    const template = await this.templateRepository.findOne({
+      where: { id },
+      relations: ['knowledgeGroup'],
+    });
+
+    if (!template) {
+      throw new NotFoundException(`Template with ID "${id}" not found`);
+    }
+
+    // Check permission using TenantService
+    const hasAccess = await this.tenantService.canAccessTenant(
+      userId,
+      template.tenantId,
+      tenantId,
+    );
+    if (!hasAccess) {
+      throw new ForbiddenException(
+        `You do not have permission to access this template`,
+      );
+    }
+
+    return template;
+  }
+
+  async update(
+    id: string,
+    updateDto: UpdateTemplateDto,
+    userId: string,
+    tenantId: string,
+  ): Promise<AssessmentTemplate> {
+    const template = await this.findOne(id, userId, tenantId);
+    Object.assign(template, updateDto);
+    return this.templateRepository.save(template);
+  }
+
+  async remove(id: string, userId: string, tenantId: string): Promise<void> {
+    const template = await this.findOne(id, userId, tenantId);
+    // Soft delete by setting isActive to false
+    template.isActive = false;
+    await this.templateRepository.save(template);
+  }
+}