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/.env.sample

@@ -0,0 +1,48 @@
+PORT=3001
+# IMPORTANT: Must change the following in production environment
+# Database path
+DATABASE_PATH=./data/metadata.db
+
+# Service host configuration (use actual server address in production)
+ELASTICSEARCH_HOST=http://127.0.0.1:9200    # Change for production
+TIKA_HOST=http://127.0.0.1:9998            # Change for production
+LIBREOFFICE_URL=http://127.0.0.1:8100       # Change for production
+JWT_SECRET=your-super-secure-jwt-secret-key-change-it-in-production
+
+# File Upload Configuration
+UPLOAD_FILE_PATH=./uploads
+MAX_FILE_SIZE=104857600
+TEMP_DIR=./temp
+
+# Vector Dimensions Configuration
+# Must match the output dimensions of your embedding model
+# Common values: 2560 (text-embedding-3-large), 1536 (text-embedding-3-small), 2048 (custom)
+DEFAULT_VECTOR_DIMENSIONS=2048
+
+# Chunk Size Limits Configuration
+# Maximum chunk size (tokens) - env var limit (highest priority)
+# Set according to your embedding model
+# OpenAI text-embedding-3-large: 8191
+# OpenAI text-embedding-3-small: 8191
+# Google Gemini embedding-001: 2048
+MAX_CHUNK_SIZE=8191
+
+# Maximum chunk overlap (tokens) - env var limit
+# Recommended: 10-20% of chunk size
+MAX_OVERLAP_SIZE=200
+
+# Memory Management Configuration
+# Default language for the system (zh, en, ja)
+# If not set, defaults to 'en'
+DEFAULT_LANGUAGE=en
+
+# Memory usage limit (MB). Triggers wait or forced GC when exceeded
+MAX_MEMORY_USAGE_MB=1024
+# Batch processing size (chunk count)
+CHUNK_BATCH_SIZE=100
+# Forced GC threshold (MB)
+GC_THRESHOLD_MB=800
+
+# Frontend settings
+# ALLOWED_HOSTS - Comma-separated list of hosts allowed for API connection
+# Set in frontend .env file as REACT_APP_ALLOWED_HOSTS