feat: 实现后端多环境配置机制

- 使用 toml crate 替代 config crate 直接读取配置文件
- 创建 config/default.toml、config/development.toml、config/production.toml
- 重写 config.rs 支持多环境配置加载
- 增强 deploy.sh 支持 development/production 环境参数
- 更新 IMPROVEMENTS.md 标记环境区分完成

src/models.rs

@@ -149,7 +149,11 @@ pub struct WeatherData {
     #[sqlx(rename = "averagewindspeed")]
     pub average_wind_speed: f64,
 
-    #[serde(rename = "calculatedWindSpeed", alias = "calculated_wind_speed", alias = "calculatedwindspeed")]
+    #[serde(
+        rename = "calculatedWindSpeed",
+        alias = "calculated_wind_speed",
+        alias = "calculatedwindspeed"
+    )]
     #[sqlx(rename = "calculatedwindspeed")]
     pub calculated_wind_speed: Option<f64>, // 这个已经是 Option，很好
 
@@ -305,6 +309,7 @@ pub struct AppState {
     pub jwt_secret: String,
     pub wechat_appid: String,
     pub wechat_secret: String,
+    pub free_user_data_limit: i32,
 }
 
 impl AppState {
@@ -316,6 +321,9 @@ impl AppState {
                 .map_err(|_| "环境变量WECHAT_APPID未设置".to_string())?,
             wechat_secret: std::env::var("WECHAT_SECRET")
                 .map_err(|_| "环境变量WECHAT_SECRET未设置".to_string())?,
+            free_user_data_limit: std::env::var("FREE_USER_DATA_LIMIT")
+                .map(|v| v.parse().unwrap_or(20))
+                .unwrap_or(20),
         })
     }
 }