chore(deploy): 本地部署脚本、容器配置与运行说明

PostgreSQL/pgvector 与 Redis 独立容器，后端、worker、前端可一键启停；不覆盖既有密钥。

backend/scripts/start.sh

@@ -0,0 +1,48 @@
+#!/bin/bash
+set -e
+
+# Set environment variable to prevent tokenizer deadlock warnings
+export TOKENIZERS_PARALLELISM=false
+
+# Wait for PostgreSQL to be ready
+echo "Waiting for PostgreSQL..."
+while ! nc -z db 5432; do
+  sleep 0.1
+done
+echo "PostgreSQL is ready!"
+
+# Check if Firebase credentials exist, but don't create them if missing
+if [ ! -z "$FIREBASE_CREDENTIALS" ] && [ ! -f "$FIREBASE_CREDENTIALS" ]; then
+    echo "Warning: Firebase credentials file not found at $FIREBASE_CREDENTIALS. Continuing without Firebase credentials..."
+fi
+
+
+
+# Preload embedding models to avoid runtime issues
+echo "Preloading embedding models..."
+python scripts/preload_models.py
+if [ $? -eq 0 ]; then
+    echo "Models preloaded successfully!"
+else
+    echo "Warning: Model preloading failed. Continuing anyway..."
+fi
+
+# Run migrations
+echo "Running database migrations..."
+alembic upgrade head
+
+# Use only 2 workers to reduce resource usage and database connection issues
+WORKERS=1
+
+# Start the application with Gunicorn
+echo "Starting FastAPI application with Gunicorn ($WORKERS workers)..."
+gunicorn app.main:app \
+    --workers $WORKERS \
+    --worker-class uvicorn.workers.UvicornWorker \
+    --bind 0.0.0.0:8000 \
+    --timeout 120 \
+    --keep-alive 5 \
+    --log-level info \
+    --access-logfile - \
+    --error-logfile - \
+    --preload