refactor: 拆分 system.rs 大文件，将 email_templates/proxy_errors/system_config 下沉到 shared 层

- 删除 1666 行的 admin/system/shared/system.rs，按职责拆分到独立模块
- 新增 handlers/shared/email_templates.rs 和 system_config_values.rs 存放跨层共用的模板/配置工具函数
- 新增 admin/system/shared/email_templates.rs 存放 admin 专用的模板操作逻辑
- 新增 admin/shared/proxy_errors.rs 存放 build_proxy_error_response
- 清理 public/system_modules_helpers 中不属于 public 层的导出
- 新增架构测试守护模块归属边界

apps/aether-gateway/src/handlers/admin/system/shared/email_templates.rs

@@ -0,0 +1,224 @@
+use crate::handlers::shared::{
+    admin_email_template_definition, admin_email_template_html_key,
+    admin_email_template_subject_key, read_admin_email_template_payload,
+    render_admin_email_template_html, system_config_string,
+};
+use crate::{AppState, GatewayError};
+use axum::body::Bytes;
+use axum::http;
+use serde_json::json;
+
+pub(crate) async fn build_admin_email_templates_payload(
+    state: &AppState,
+) -> Result<serde_json::Value, GatewayError> {
+    let mut templates = Vec::new();
+    for template_type in ["verification", "password_reset"] {
+        if let Some(payload) = read_admin_email_template_payload(state, template_type).await? {
+            let mut payload = payload;
+            if let Some(object) = payload.as_object_mut() {
+                object.remove("default_subject");
+                object.remove("default_html");
+            }
+            templates.push(payload);
+        }
+    }
+
+    Ok(json!({ "templates": templates }))
+}
+
+pub(crate) async fn build_admin_email_template_payload(
+    state: &AppState,
+    template_type: &str,
+) -> Result<Result<serde_json::Value, (http::StatusCode, serde_json::Value)>, GatewayError> {
+    let Some(payload) = read_admin_email_template_payload(state, template_type).await? else {
+        return Ok(Err((
+            http::StatusCode::NOT_FOUND,
+            json!({ "detail": format!("模板类型 '{template_type}' 不存在") }),
+        )));
+    };
+    Ok(Ok(payload))
+}
+
+pub(crate) async fn apply_admin_email_template_update(
+    state: &AppState,
+    template_type: &str,
+    request_body: &Bytes,
+) -> Result<Result<serde_json::Value, (http::StatusCode, serde_json::Value)>, GatewayError> {
+    let Some(definition) = admin_email_template_definition(template_type) else {
+        return Ok(Err((
+            http::StatusCode::NOT_FOUND,
+            json!({ "detail": format!("模板类型 '{template_type}' 不存在") }),
+        )));
+    };
+    let payload = match serde_json::from_slice::<serde_json::Value>(request_body) {
+        Ok(serde_json::Value::Object(payload)) => payload,
+        _ => {
+            return Ok(Err((
+                http::StatusCode::BAD_REQUEST,
+                json!({ "detail": "请求数据验证失败" }),
+            )));
+        }
+    };
+    let subject = match payload.get("subject") {
+        Some(serde_json::Value::String(value)) => Some(value.clone()),
+        Some(serde_json::Value::Null) | None => None,
+        Some(_) => {
+            return Ok(Err((
+                http::StatusCode::BAD_REQUEST,
+                json!({ "detail": "请求数据验证失败" }),
+            )));
+        }
+    };
+    let html = match payload.get("html") {
+        Some(serde_json::Value::String(value)) => Some(value.clone()),
+        Some(serde_json::Value::Null) | None => None,
+        Some(_) => {
+            return Ok(Err((
+                http::StatusCode::BAD_REQUEST,
+                json!({ "detail": "请求数据验证失败" }),
+            )));
+        }
+    };
+
+    if subject.is_none() && html.is_none() {
+        return Ok(Err((
+            http::StatusCode::BAD_REQUEST,
+            json!({ "detail": "请提供 subject 或 html" }),
+        )));
+    }
+
+    let subject_key = admin_email_template_subject_key(definition.template_type);
+    let html_key = admin_email_template_html_key(definition.template_type);
+
+    if let Some(subject) = subject {
+        if subject.is_empty() {
+            let _ = state.delete_system_config_value(&subject_key).await?;
+        } else {
+            let _ = state
+                .upsert_system_config_json_value(&subject_key, &json!(subject), None)
+                .await?;
+        }
+    }
+
+    if let Some(html) = html {
+        if html.is_empty() {
+            let _ = state.delete_system_config_value(&html_key).await?;
+        } else {
+            let _ = state
+                .upsert_system_config_json_value(&html_key, &json!(html), None)
+                .await?;
+        }
+    }
+
+    Ok(Ok(json!({ "message": "模板保存成功" })))
+}
+
+pub(crate) async fn preview_admin_email_template(
+    state: &AppState,
+    template_type: &str,
+    request_body: Option<&Bytes>,
+) -> Result<Result<serde_json::Value, (http::StatusCode, serde_json::Value)>, GatewayError> {
+    let Some(definition) = admin_email_template_definition(template_type) else {
+        return Ok(Err((
+            http::StatusCode::NOT_FOUND,
+            json!({ "detail": format!("模板类型 '{template_type}' 不存在") }),
+        )));
+    };
+
+    let payload = match request_body {
+        Some(bytes) => match serde_json::from_slice::<serde_json::Value>(bytes) {
+            Ok(serde_json::Value::Object(payload)) => payload,
+            Ok(serde_json::Value::Null) => serde_json::Map::new(),
+            _ => {
+                return Ok(Err((
+                    http::StatusCode::BAD_REQUEST,
+                    json!({ "detail": "请求数据验证失败" }),
+                )));
+            }
+        },
+        None => serde_json::Map::new(),
+    };
+
+    let resolved = read_admin_email_template_payload(state, definition.template_type)
+        .await?
+        .expect("validated template type should exist");
+    let resolved_html = resolved["html"].as_str().unwrap_or(definition.default_html);
+    let html = payload
+        .get("html")
+        .and_then(|value| value.as_str())
+        .filter(|value| !value.is_empty())
+        .unwrap_or(resolved_html);
+
+    let email_app_name = state
+        .read_system_config_json_value("email_app_name")
+        .await?;
+    let smtp_from_name = state
+        .read_system_config_json_value("smtp_from_name")
+        .await?;
+    let app_name = system_config_string(email_app_name.as_ref())
+        .or_else(|| system_config_string(smtp_from_name.as_ref()))
+        .unwrap_or_else(|| "Aether".to_string());
+
+    let mut defaults = std::collections::BTreeMap::new();
+    defaults.insert("app_name".to_string(), app_name);
+    defaults.insert("code".to_string(), "123456".to_string());
+    defaults.insert("expire_minutes".to_string(), "30".to_string());
+    defaults.insert("email".to_string(), "[email protected]".to_string());
+    defaults.insert(
+        "reset_link".to_string(),
+        "https://example.com/reset?token=abc123".to_string(),
+    );
+
+    let preview_variables = definition
+        .variables
+        .iter()
+        .map(|key| {
+            let value = payload
+                .get(*key)
+                .map(|value| match value {
+                    serde_json::Value::String(value) => value.clone(),
+                    serde_json::Value::Null => "None".to_string(),
+                    _ => value.to_string(),
+                })
+                .or_else(|| defaults.get(*key).cloned())
+                .unwrap_or_else(|| format!("{{{{{key}}}}}"));
+            ((*key).to_string(), value)
+        })
+        .collect::<std::collections::BTreeMap<_, _>>();
+
+    let rendered_html = render_admin_email_template_html(html, &preview_variables)?;
+
+    Ok(Ok(json!({
+        "html": rendered_html,
+        "variables": preview_variables,
+    })))
+}
+
+pub(crate) async fn reset_admin_email_template(
+    state: &AppState,
+    template_type: &str,
+) -> Result<Result<serde_json::Value, (http::StatusCode, serde_json::Value)>, GatewayError> {
+    let Some(definition) = admin_email_template_definition(template_type) else {
+        return Ok(Err((
+            http::StatusCode::NOT_FOUND,
+            json!({ "detail": format!("模板类型 '{template_type}' 不存在") }),
+        )));
+    };
+
+    let _ = state
+        .delete_system_config_value(&admin_email_template_subject_key(definition.template_type))
+        .await?;
+    let _ = state
+        .delete_system_config_value(&admin_email_template_html_key(definition.template_type))
+        .await?;
+
+    Ok(Ok(json!({
+        "message": "模板已重置为默认值",
+        "template": {
+            "type": definition.template_type,
+            "name": definition.name,
+            "subject": definition.default_subject,
+            "html": definition.default_html,
+        }
+    })))
+}

apps/aether-gateway/src/handlers/admin/system/shared/mod.rs

@@ -1,9 +1,14 @@
 mod configs;
+mod email_templates;
 mod modules;
 mod paths;
 mod settings;
 
 pub(crate) use self::configs::*;
+pub(crate) use self::email_templates::{
+    apply_admin_email_template_update, build_admin_email_template_payload,
+    build_admin_email_templates_payload, preview_admin_email_template, reset_admin_email_template,
+};
 pub(crate) use self::modules::*;
 pub(crate) use self::paths::*;
 pub(crate) use self::settings::*;

apps/aether-gateway/src/handlers/admin/system/shared/modules.rs

@@ -1,4 +1,4 @@
-use crate::handlers::public::{module_available_from_env, system_config_bool};
+use crate::handlers::shared::{module_available_from_env, system_config_bool};
 use crate::{AppState, GatewayError};
 use serde_json::json;
 

apps/aether-gateway/src/handlers/admin/system/shared/settings.rs

@@ -1,4 +1,4 @@
-use crate::handlers::public::{system_config_bool, system_config_string};
+use crate::handlers::shared::{system_config_bool, system_config_string};
 use crate::{AppState, GatewayError};
 use axum::body::Bytes;
 use axum::http;