feat(ai): Day 8 — 会话 CRUD API + chat_handler session 模式

- 新增 4 个会话端点: POST/GET /ai/chat/sessions, PUT rename, POST close
- ChatRequest 增加 session_id 字段（Optional，向后兼容）
- session_id 模式: DB 加载历史 + 持久化消息 + Tool 调用日志写入
- 无 session_id 时保持原有 history 数组模式不变
- 权限: ai.chat.session.list / ai.chat.session.manage

crates/erp-ai/src/handler/chat_handler.rs

@@ -27,6 +27,8 @@ pub struct ChatRequest {
     pub history: Option<Vec<ChatHistoryItem>>,
     /// 可选：关联患者 ID（从用户档案中获取）
     pub patient_id: Option<uuid::Uuid>,
+    /// 可选：会话 ID（传入时走会话持久化模式）
+    pub session_id: Option<uuid::Uuid>,
 }
 
 #[derive(Debug, Deserialize, Serialize, utoipa::ToSchema)]
@@ -98,8 +100,34 @@ where
     // 构建 Agent 消息历史
     let mut messages = vec![];
 
-    // 将前端传来的历史转换为 Agent ChatMessage
+    // session_id 模式：从 DB 加载历史
-    if let Some(ref hist) = body.history {
+    if let Some(sid) = body.session_id {
+        let db_messages = ai_state
+            .chat_message
+            .list_messages(ctx.tenant_id, sid, 50)
+            .await
+            .unwrap_or_default();
+        for m in &db_messages {
+            if m.deleted_at.is_some() {
+                continue;
+            }
+            let role = match m.role.as_str() {
+                "user" => ChatMessageRole::User,
+                "tool" => ChatMessageRole::Tool,
+                _ => ChatMessageRole::Assistant,
+            };
+            let tool_calls: Option<Vec<crate::dto::ToolCall>> = m
+                .tool_calls
+                .as_ref()
+                .and_then(|v| serde_json::from_value(v.clone()).ok());
+            messages.push(ChatMessage {
+                role,
+                content: m.content.clone().unwrap_or_default(),
+                tool_calls,
+                tool_call_id: m.tool_call_id.clone(),
+            });
+        }
+    } else if let Some(ref hist) = body.history {
         let filtered: Vec<&ChatHistoryItem> = hist
             .iter()
             .filter(|h| h.role == "user" || h.role == "assistant")
@@ -250,6 +278,69 @@ where
         tracing::warn!(error = %e, "Failed to log chat usage");
     }
 
+    // session_id 模式：持久化消息
+    let assistant_uuid = uuid::Uuid::parse_str(&message_id).unwrap_or(uuid::Uuid::now_v7());
+    if let Some(sid) = body.session_id {
+        use crate::service::chat_message::{SaveMessageParams, SaveToolCallLogParams};
+
+        // 保存用户消息
+        if let Err(e) = ai_state
+            .chat_message
+            .save_message(SaveMessageParams {
+                tenant_id: ctx.tenant_id,
+                session_id: sid,
+                role: "user".to_string(),
+                content: Some(message.to_string()),
+                tool_calls: None,
+                tool_call_id: None,
+                token_count: None,
+                user_id: ctx.user_id,
+            })
+            .await
+        {
+            tracing::warn!(error = %e, "Failed to save user message to session");
+        }
+
+        // 保存助手回复
+        if let Err(e) = ai_state
+            .chat_message
+            .save_message(SaveMessageParams {
+                tenant_id: ctx.tenant_id,
+                session_id: sid,
+                role: "assistant".to_string(),
+                content: Some(result.reply.clone()),
+                tool_calls: None,
+                tool_call_id: None,
+                token_count: Some((result.total_input_tokens + result.total_output_tokens) as i32),
+                user_id: ctx.user_id,
+            })
+            .await
+        {
+            tracing::warn!(error = %e, "Failed to save assistant message to session");
+        }
+
+        // 保存 Tool 调用日志
+        for tc_log in &result.tool_calls {
+            if let Err(e) = ai_state
+                .chat_message
+                .save_tool_call_log(SaveToolCallLogParams {
+                    tenant_id: ctx.tenant_id,
+                    session_id: sid,
+                    message_id: assistant_uuid,
+                    tool_name: tc_log.tool_name.clone(),
+                    parameters: None,
+                    result_summary: None,
+                    execution_ms: tc_log.duration_ms as i32,
+                    success: tc_log.success,
+                    user_id: ctx.user_id,
+                })
+                .await
+            {
+                tracing::warn!(error = %e, tool = %tc_log.tool_name, "Failed to save tool call log");
+            }
+        }
+    }
+
     Ok(Json(ApiResponse::ok(ChatResponse {
         reply: result.reply,
         message_id,
@@ -261,3 +352,163 @@ where
         },
     })))
 }
+
+// === 会话 CRUD ===
+
+#[derive(Debug, Serialize, utoipa::ToSchema)]
+pub struct SessionResponse {
+    pub id: uuid::Uuid,
+    pub title: Option<String>,
+    pub patient_id: Option<uuid::Uuid>,
+    pub status: String,
+    pub created_at: String,
+    pub updated_at: String,
+}
+
+impl From<crate::entity::ai_chat_session::Model> for SessionResponse {
+    fn from(m: crate::entity::ai_chat_session::Model) -> Self {
+        Self {
+            id: m.id,
+            title: m.title,
+            patient_id: m.patient_id,
+            status: m.status,
+            created_at: m.created_at.to_rfc3339(),
+            updated_at: m.updated_at.to_rfc3339(),
+        }
+    }
+}
+
+#[derive(Debug, Deserialize, utoipa::ToSchema)]
+pub struct CreateSessionRequest {
+    pub patient_id: Option<uuid::Uuid>,
+    pub title: Option<String>,
+}
+
+#[derive(Debug, Deserialize, utoipa::ToSchema)]
+pub struct RenameSessionRequest {
+    pub title: String,
+}
+
+#[utoipa::path(
+    post,
+    path = "/ai/chat/sessions",
+    request_body = CreateSessionRequest,
+    responses((status = 200, description = "创建会话")),
+    tag = "AI 会话",
+    security(("bearer_auth" = [])),
+)]
+pub async fn create_session<S>(
+    Extension(ctx): Extension<TenantContext>,
+    State(state): State<S>,
+    Json(body): Json<CreateSessionRequest>,
+) -> Result<Json<ApiResponse<SessionResponse>>, erp_core::error::AppError>
+where
+    AiState: FromRef<S>,
+    S: Clone + Send + Sync + 'static,
+{
+    require_permission(&ctx, "ai.chat.session.manage")?;
+    let ai_state = AiState::from_ref(&state);
+    let session = ai_state
+        .chat_session
+        .create(ctx.tenant_id, ctx.user_id, body.patient_id, body.title)
+        .await
+        .map_err(|e| {
+            tracing::error!(error = %e, "Failed to create session");
+            erp_core::error::AppError::Internal("创建会话失败".into())
+        })?;
+    Ok(Json(ApiResponse::ok(SessionResponse::from(session))))
+}
+
+#[utoipa::path(
+    get,
+    path = "/ai/chat/sessions",
+    responses((status = 200, description = "会话列表")),
+    tag = "AI 会话",
+    security(("bearer_auth" = [])),
+)]
+pub async fn list_sessions<S>(
+    Extension(ctx): Extension<TenantContext>,
+    State(state): State<S>,
+) -> Result<Json<ApiResponse<Vec<SessionResponse>>>, erp_core::error::AppError>
+where
+    AiState: FromRef<S>,
+    S: Clone + Send + Sync + 'static,
+{
+    require_permission(&ctx, "ai.chat.session.list")?;
+    let ai_state = AiState::from_ref(&state);
+    let sessions = ai_state
+        .chat_session
+        .list(ctx.tenant_id, ctx.user_id)
+        .await
+        .map_err(|e| {
+            tracing::error!(error = %e, "Failed to list sessions");
+            erp_core::error::AppError::Internal("获取会话列表失败".into())
+        })?;
+    let resp: Vec<SessionResponse> = sessions.into_iter().map(SessionResponse::from).collect();
+    Ok(Json(ApiResponse::ok(resp)))
+}
+
+#[utoipa::path(
+    put,
+    path = "/ai/chat/sessions/{session_id}/rename",
+    responses((status = 200, description = "重命名成功")),
+    tag = "AI 会话",
+    security(("bearer_auth" = [])),
+)]
+pub async fn rename_session<S>(
+    Extension(ctx): Extension<TenantContext>,
+    State(state): State<S>,
+    axum::extract::Path(session_id): axum::extract::Path<uuid::Uuid>,
+    Json(body): Json<RenameSessionRequest>,
+) -> Result<Json<ApiResponse<()>>, erp_core::error::AppError>
+where
+    AiState: FromRef<S>,
+    S: Clone + Send + Sync + 'static,
+{
+    require_permission(&ctx, "ai.chat.session.manage")?;
+    let ai_state = AiState::from_ref(&state);
+    let ok = ai_state
+        .chat_session
+        .rename(ctx.tenant_id, session_id, body.title)
+        .await
+        .map_err(|e| {
+            tracing::error!(error = %e, "Failed to rename session");
+            erp_core::error::AppError::Internal("重命名会话失败".into())
+        })?;
+    if !ok {
+        return Err(erp_core::error::AppError::Validation("会话不存在".into()));
+    }
+    Ok(Json(ApiResponse::ok(())))
+}
+
+#[utoipa::path(
+    post,
+    path = "/ai/chat/sessions/{session_id}/close",
+    responses((status = 200, description = "关闭成功")),
+    tag = "AI 会话",
+    security(("bearer_auth" = [])),
+)]
+pub async fn close_session<S>(
+    Extension(ctx): Extension<TenantContext>,
+    State(state): State<S>,
+    axum::extract::Path(session_id): axum::extract::Path<uuid::Uuid>,
+) -> Result<Json<ApiResponse<()>>, erp_core::error::AppError>
+where
+    AiState: FromRef<S>,
+    S: Clone + Send + Sync + 'static,
+{
+    require_permission(&ctx, "ai.chat.session.manage")?;
+    let ai_state = AiState::from_ref(&state);
+    let ok = ai_state
+        .chat_session
+        .close(ctx.tenant_id, session_id)
+        .await
+        .map_err(|e| {
+            tracing::error!(error = %e, "Failed to close session");
+            erp_core::error::AppError::Internal("关闭会话失败".into())
+        })?;
+    if !ok {
+        return Err(erp_core::error::AppError::Validation("会话不存在".into()));
+    }
+    Ok(Json(ApiResponse::ok(())))
+}

crates/erp-ai/src/module.rs

@@ -431,6 +431,22 @@ impl AiModule {
                 "/ai/chat",
                 axum::routing::post(crate::handler::chat_handler::chat),
             )
+            .route(
+                "/ai/chat/sessions",
+                axum::routing::post(crate::handler::chat_handler::create_session),
+            )
+            .route(
+                "/ai/chat/sessions",
+                axum::routing::get(crate::handler::chat_handler::list_sessions),
+            )
+            .route(
+                "/ai/chat/sessions/{session_id}/rename",
+                axum::routing::put(crate::handler::chat_handler::rename_session),
+            )
+            .route(
+                "/ai/chat/sessions/{session_id}/close",
+                axum::routing::post(crate::handler::chat_handler::close_session),
+            )
             .route(
                 "/ai/config",
                 axum::routing::get(crate::handler::config_handler::get_config),