docs: Add model setup documentation and script

- Add models/README.md with model file information
- Add scripts/setup-models.sh for easy model linking
- Document how to obtain and setup model files

models/README.md

@@ -0,0 +1,43 @@
+# 模型文件目录
+
+此目录用于存放 AI 检测模型文件。
+
+## 模型清单
+
+| 模型 | 文件名 | 来源 | 大小 |
+|------|--------|------|------|
+| 火灾检测 | `fire_detection/best.pt` | fire_detection/models/best.pt | ~61MB |
+| 安全帽检测 | `helmet_detection/yolov8n.pt` | yolov/yolov8n.pt | ~6MB |
+| 人群检测 | `crowd_detection/yolov8l.pt` | behavior_detection/Crowd-Gathering/models/yolov8l.pt | ~100MB |
+| 抽烟检测 | `smoking_detection/smoking_yolov8n.pt` | behavior_detection/smoker-detection/models/smoking_yolov8n.pt | ~6MB |
+| 徘徊检测 | `loitering_detection/yolov8n.pt` | behavior_detection/Loitering-Detection/yolov8n.pt | ~6MB |
+
+## 设置模型
+
+### 方式1: 符号链接（开发环境）
+```bash
+# 在项目根目录执行
+ln -sf /path/to/fire_detection/models/best.pt models/fire_detection/
+ln -sf /path/to/yolov/yolov8n.pt models/helmet_detection/
+ln -sf /path/to/behavior_detection/Crowd-Gathering/models/yolov8l.pt models/crowd_detection/
+ln -sf /path/to/behavior_detection/smoker-detection/models/smoking_yolov8n.pt models/smoking_detection/
+ln -sf /path/to/behavior_detection/Loitering-Detection/yolov8n.pt models/loitering_detection/
+```
+
+### 方式2: 复制文件
+```bash
+cp /path/to/fire_detection/models/best.pt models/fire_detection/
+cp /path/to/yolov/yolov8n.pt models/helmet_detection/
+cp /path/to/behavior_detection/Crowd-Gathering/models/yolov8l.pt models/crowd_detection/
+cp /path/to/behavior_detection/smoker-detection/models/smoking_yolov8n.pt models/smoking_detection/
+cp /path/to/behavior_detection/Loitering-Detection/yolov8n.pt models/loitering_detection/
+```
+
+### 方式3: 使用初始化脚本
+```bash
+bash scripts/setup-models.sh
+```
+
+## 注意
+
+模型文件较大，未包含在 Git 仓库中。请从原始位置复制或创建符号链接。