Refactor project structure by removing Docker support and updating environment configuration

- Deleted docker-compose.yml, backend Dockerfile, frontend Dockerfile, and nginx configuration to streamline project setup.
- Updated .env.example to reorganize LLM and ZEP API configurations for clarity and ease of use.
- Enhanced README.md to reflect changes in project structure and provide clearer setup instructions.

backend/Dockerfile

@@ -1,59 +0,0 @@
-# MiroFish Backend Dockerfile
-# Multi-stage build for smaller image size
-
-# ============= Build Stage =============
-FROM python:3.11-slim AS builder
-
-WORKDIR /app
-
-# 安装构建依赖
-RUN apt-get update && apt-get install -y --no-install-recommends \
-    build-essential \
-    && rm -rf /var/lib/apt/lists/*
-
-# 复制依赖文件
-COPY requirements.txt .
-
-# 创建虚拟环境并安装依赖
-RUN python -m venv /opt/venv
-ENV PATH="/opt/venv/bin:$PATH"
-
-RUN pip install --no-cache-dir --upgrade pip && \
-    pip install --no-cache-dir -r requirements.txt
-
-# ============= Production Stage =============
-FROM python:3.11-slim
-
-WORKDIR /app
-
-# 安装运行时依赖
-RUN apt-get update && apt-get install -y --no-install-recommends \
-    curl \
-    && rm -rf /var/lib/apt/lists/*
-
-# 从 builder 复制虚拟环境
-COPY --from=builder /opt/venv /opt/venv
-ENV PATH="/opt/venv/bin:$PATH"
-
-# 复制应用代码
-COPY app/ ./app/
-COPY scripts/ ./scripts/
-COPY run.py .
-
-# 创建上传目录
-RUN mkdir -p uploads/simulations uploads/reports
-
-# 设置环境变量
-ENV PYTHONUNBUFFERED=1
-ENV FLASK_HOST=0.0.0.0
-ENV FLASK_PORT=5001
-
-# 暴露端口
-EXPOSE 5001
-
-# 健康检查
-HEALTHCHECK --interval=30s --timeout=10s --start-period=5s --retries=3 \
-    CMD curl -f http://localhost:5001/health || exit 1
-
-# 启动命令
-CMD ["python", "run.py"]