feat: initialize Nuanji (Warm Notes) project

- Base platform from base.git (ERP base: auth, core, config, message, workflow, plugin)
- Created erp-diary module skeleton (lib.rs, dto.rs, error.rs, event.rs, state.rs)
- Integrated erp-diary into workspace and erp-server
- Added DiaryModule registration in main.rs
- Added DiaryState FromRef in state.rs
- Diary routes mounted (empty routes, ready for implementation)
- Product design spec v1.2 preserved in docs/
- Implementation plan preserved in plans/

Cargo check: OK
Cargo test: OK (78+ base tests passing)

crates/erp-message/src/handler/subscription_handler.rs

@@ -0,0 +1,60 @@
+use axum::Json;
+use axum::extract::FromRef;
+use axum::extract::{Extension, State};
+
+use erp_core::error::AppError;
+use erp_core::types::{ApiResponse, TenantContext};
+
+use crate::dto::UpdateSubscriptionReq;
+use crate::message_state::MessageState;
+use crate::service::subscription_service::SubscriptionService;
+
+#[utoipa::path(
+    get,
+    path = "/api/v1/message-subscriptions",
+    responses(
+        (status = 200, description = "成功", body = ApiResponse<crate::dto::MessageSubscriptionResp>),
+        (status = 401, description = "未授权"),
+    ),
+    security(("bearer_auth" = [])),
+    tag = "消息订阅"
+)]
+/// 获取当前用户的消息订阅偏好。
+pub async fn get_subscription<S>(
+    State(_state): State<MessageState>,
+    Extension(ctx): Extension<TenantContext>,
+) -> Result<Json<ApiResponse<crate::dto::MessageSubscriptionResp>>, AppError>
+where
+    MessageState: FromRef<S>,
+    S: Clone + Send + Sync + 'static,
+{
+    let resp = SubscriptionService::get(ctx.tenant_id, ctx.user_id, &_state.db).await?;
+    Ok(Json(ApiResponse::ok(resp)))
+}
+
+#[utoipa::path(
+    put,
+    path = "/api/v1/message-subscriptions",
+    request_body = UpdateSubscriptionReq,
+    responses(
+        (status = 200, description = "成功", body = ApiResponse<crate::dto::MessageSubscriptionResp>),
+        (status = 401, description = "未授权"),
+        (status = 403, description = "权限不足"),
+    ),
+    security(("bearer_auth" = [])),
+    tag = "消息订阅"
+)]
+/// 更新消息订阅偏好。
+pub async fn update_subscription<S>(
+    State(_state): State<MessageState>,
+    Extension(ctx): Extension<TenantContext>,
+    Json(req): Json<UpdateSubscriptionReq>,
+) -> Result<Json<ApiResponse<crate::dto::MessageSubscriptionResp>>, AppError>
+where
+    MessageState: FromRef<S>,
+    S: Clone + Send + Sync + 'static,
+{
+    let resp = SubscriptionService::upsert(ctx.tenant_id, ctx.user_id, &req, &_state.db).await?;
+
+    Ok(Json(ApiResponse::ok(resp)))
+}