feat: 初始化ERP平台底座项目结构

- 添加基础crate结构(erp-core, erp-common)
- 实现核心模块trait和事件总线
- 配置Docker开发环境(PostgreSQL+Redis)
- 添加Tauri桌面端基础框架
- 设置CI/CD工作流
- 编写项目协作规范文档(CLAUDE.md)

crates/erp-server/src/config.rs

@@ -0,0 +1,50 @@
+use serde::Deserialize;
+
+#[derive(Debug, Deserialize)]
+pub struct AppConfig {
+    pub server: ServerConfig,
+    pub database: DatabaseConfig,
+    pub redis: RedisConfig,
+    pub jwt: JwtConfig,
+    pub log: LogConfig,
+}
+
+#[derive(Debug, Deserialize)]
+pub struct ServerConfig {
+    pub host: String,
+    pub port: u16,
+}
+
+#[derive(Debug, Deserialize)]
+pub struct DatabaseConfig {
+    pub url: String,
+    pub max_connections: u32,
+    pub min_connections: u32,
+}
+
+#[derive(Debug, Deserialize)]
+pub struct RedisConfig {
+    pub url: String,
+}
+
+#[derive(Debug, Deserialize)]
+pub struct JwtConfig {
+    pub secret: String,
+    pub access_token_ttl: String,
+    pub refresh_token_ttl: String,
+}
+
+#[derive(Debug, Deserialize)]
+pub struct LogConfig {
+    pub level: String,
+}
+
+impl AppConfig {
+    pub fn load() -> anyhow::Result<Self> {
+        let config = config::Config::builder()
+            .add_source(config::File::with_name("config/default"))
+            .add_source(config::Environment::with_prefix("ERP").separator("__"))
+            .build()?;
+        Ok(config.try_deserialize()?)
+    }
+}