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/knowledge-group/knowledge-group.controller.ts

@@ -0,0 +1,84 @@
+import {
+  Controller,
+  Get,
+  Post,
+  Put,
+  Delete,
+  Body,
+  Param,
+  UseGuards,
+  Request,
+  Query,
+} from '@nestjs/common';
+import { CombinedAuthGuard } from '../auth/combined-auth.guard';
+import { RolesGuard } from '../auth/roles.guard';
+import { Roles } from '../auth/roles.decorator';
+import { UserRole } from '../user/user-role.enum';
+import {
+  KnowledgeGroupService,
+  CreateGroupDto,
+  UpdateGroupDto,
+} from './knowledge-group.service';
+import { I18nService } from '../i18n/i18n.service';
+
+@Controller('knowledge-groups')
+@UseGuards(CombinedAuthGuard, RolesGuard)
+export class KnowledgeGroupController {
+  constructor(
+    private readonly groupService: KnowledgeGroupService,
+    private readonly i18nService: I18nService,
+  ) {}
+
+  @Get()
+  async findAll(@Request() req) {
+    // All users can see all groups for their tenant (returns tree structure)
+    return await this.groupService.findAll(req.user.id, req.user.tenantId);
+  }
+
+  @Get(':id')
+  async findOne(@Param('id') id: string, @Request() req) {
+    return await this.groupService.findOne(id, req.user.id, req.user.tenantId);
+  }
+
+  @Post()
+  @Roles(UserRole.TENANT_ADMIN, UserRole.SUPER_ADMIN)
+  async create(@Body() createGroupDto: CreateGroupDto, @Request() req) {
+    return await this.groupService.create(
+      req.user.id,
+      req.user.tenantId,
+      createGroupDto,
+    );
+  }
+
+  @Put(':id')
+  @Roles(UserRole.TENANT_ADMIN, UserRole.SUPER_ADMIN)
+  async update(
+    @Param('id') id: string,
+    @Body() updateGroupDto: UpdateGroupDto,
+    @Request() req,
+  ) {
+    return await this.groupService.update(
+      id,
+      req.user.id,
+      req.user.tenantId,
+      updateGroupDto,
+    );
+  }
+
+  @Delete(':id')
+  @Roles(UserRole.TENANT_ADMIN, UserRole.SUPER_ADMIN)
+  async remove(@Param('id') id: string, @Request() req) {
+    await this.groupService.remove(id, req.user.id, req.user.tenantId);
+    return { message: this.i18nService.getMessage('groupDeleted') };
+  }
+
+  @Get(':id/files')
+  async getGroupFiles(@Param('id') id: string, @Request() req) {
+    const files = await this.groupService.getGroupFiles(
+      id,
+      req.user.id,
+      req.user.tenantId,
+    );
+    return { files };
+  }
+}