feat(ai): Day 7 — 会话持久化 Entity + Service

- 新增 3 个 SeaORM Entity: ai_chat_session / ai_chat_message / ai_tool_call_log
- ChatSessionService: create / list / get / close / rename
- ChatMessageService: save_message / list_messages / save_tool_call_log
- 参数封装为 SaveMessageParams / SaveToolCallLogParams 避免 clippy too_many_arguments
- AiState 注册 chat_session + chat_message 服务
- erp-server main.rs 初始化注入

crates/erp-ai/src/entity/ai_chat_message.rs

@@ -0,0 +1,41 @@
+use sea_orm::entity::prelude::*;
+use serde::{Deserialize, Serialize};
+
+#[derive(Clone, Debug, PartialEq, DeriveEntityModel, Serialize, Deserialize)]
+#[sea_orm(table_name = "ai_chat_messages")]
+pub struct Model {
+    #[sea_orm(primary_key, auto_increment = false)]
+    pub id: Uuid,
+    pub tenant_id: Uuid,
+    pub session_id: Uuid,
+    pub role: String,
+    pub content: Option<String>,
+    pub tool_calls: Option<serde_json::Value>,
+    pub tool_call_id: Option<String>,
+    pub token_count: Option<i32>,
+    pub created_at: DateTimeUtc,
+    pub updated_at: DateTimeUtc,
+    pub created_by: Option<Uuid>,
+    pub updated_by: Option<Uuid>,
+    pub deleted_at: Option<DateTimeUtc>,
+    #[sea_orm(default_value = 1)]
+    pub version_lock: i32,
+}
+
+#[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
+pub enum Relation {
+    #[sea_orm(
+        belongs_to = "super::ai_chat_session::Entity",
+        from = "Column::SessionId",
+        to = "super::ai_chat_session::Column::Id"
+    )]
+    Session,
+}
+
+impl Related<super::ai_chat_session::Entity> for Entity {
+    fn to() -> RelationDef {
+        Relation::Session.def()
+    }
+}
+
+impl ActiveModelBehavior for ActiveModel {}

crates/erp-ai/src/entity/ai_chat_session.rs

@@ -0,0 +1,37 @@
+use sea_orm::entity::prelude::*;
+use serde::{Deserialize, Serialize};
+
+#[derive(Clone, Debug, PartialEq, DeriveEntityModel, Serialize, Deserialize)]
+#[sea_orm(table_name = "ai_chat_sessions")]
+pub struct Model {
+    #[sea_orm(primary_key, auto_increment = false)]
+    pub id: Uuid,
+    pub tenant_id: Uuid,
+    pub user_id: Uuid,
+    pub patient_id: Option<Uuid>,
+    pub title: Option<String>,
+    #[sea_orm(default_value = "active")]
+    pub status: String,
+    pub metadata: Option<serde_json::Value>,
+    pub created_at: DateTimeUtc,
+    pub updated_at: DateTimeUtc,
+    pub created_by: Option<Uuid>,
+    pub updated_by: Option<Uuid>,
+    pub deleted_at: Option<DateTimeUtc>,
+    #[sea_orm(default_value = 1)]
+    pub version_lock: i32,
+}
+
+#[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
+pub enum Relation {
+    #[sea_orm(has_many = "super::ai_chat_message::Entity")]
+    Messages,
+}
+
+impl Related<super::ai_chat_message::Entity> for Entity {
+    fn to() -> RelationDef {
+        Relation::Messages.def()
+    }
+}
+
+impl ActiveModelBehavior for ActiveModel {}

crates/erp-ai/src/entity/ai_tool_call_log.rs

@@ -0,0 +1,37 @@
+use sea_orm::entity::prelude::*;
+use serde::{Deserialize, Serialize};
+
+#[derive(Clone, Debug, PartialEq, DeriveEntityModel, Serialize, Deserialize)]
+#[sea_orm(table_name = "ai_tool_call_logs")]
+pub struct Model {
+    #[sea_orm(primary_key, auto_increment = false)]
+    pub id: Uuid,
+    pub tenant_id: Uuid,
+    pub session_id: Uuid,
+    pub message_id: Uuid,
+    pub tool_name: String,
+    pub parameters: Option<serde_json::Value>,
+    pub result_summary: Option<String>,
+    pub execution_ms: Option<i32>,
+    pub success: bool,
+    pub created_at: DateTimeUtc,
+    pub created_by: Option<Uuid>,
+}
+
+#[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
+pub enum Relation {
+    #[sea_orm(
+        belongs_to = "super::ai_chat_session::Entity",
+        from = "Column::SessionId",
+        to = "super::ai_chat_session::Column::Id"
+    )]
+    Session,
+}
+
+impl Related<super::ai_chat_session::Entity> for Entity {
+    fn to() -> RelationDef {
+        Relation::Session.def()
+    }
+}
+
+impl ActiveModelBehavior for ActiveModel {}

crates/erp-ai/src/entity/mod.rs

@@ -1,5 +1,7 @@
 pub mod ai_analysis;
 pub mod ai_analysis_queue;
+pub mod ai_chat_message;
+pub mod ai_chat_session;
 pub mod ai_feature_flags;
 pub mod ai_knowledge_guides;
 pub mod ai_knowledge_references;
@@ -9,6 +11,7 @@ pub mod ai_risk_threshold;
 pub mod ai_suggestion;
 pub mod ai_suggestion_feedback;
 pub mod ai_tenant_config;
+pub mod ai_tool_call_log;
 pub mod ai_usage;
 pub mod ai_usage_daily;
 pub mod copilot_chat_logs;

crates/erp-ai/src/service/chat_message.rs

@@ -0,0 +1,105 @@
+use sea_orm::{
+    ActiveModelTrait, ColumnTrait, DatabaseConnection, EntityTrait, QueryFilter, QueryOrder,
+    QuerySelect, Set,
+};
+use uuid::Uuid;
+
+use crate::entity::ai_chat_message;
+use crate::entity::ai_tool_call_log;
+
+pub struct ChatMessageService {
+    db: DatabaseConnection,
+}
+
+pub struct SaveMessageParams {
+    pub tenant_id: Uuid,
+    pub session_id: Uuid,
+    pub role: String,
+    pub content: Option<String>,
+    pub tool_calls: Option<serde_json::Value>,
+    pub tool_call_id: Option<String>,
+    pub token_count: Option<i32>,
+    pub user_id: Uuid,
+}
+
+pub struct SaveToolCallLogParams {
+    pub tenant_id: Uuid,
+    pub session_id: Uuid,
+    pub message_id: Uuid,
+    pub tool_name: String,
+    pub parameters: Option<serde_json::Value>,
+    pub result_summary: Option<String>,
+    pub execution_ms: i32,
+    pub success: bool,
+    pub user_id: Uuid,
+}
+
+impl ChatMessageService {
+    pub fn new(db: DatabaseConnection) -> Self {
+        Self { db }
+    }
+
+    pub async fn save_message(
+        &self,
+        params: SaveMessageParams,
+    ) -> Result<ai_chat_message::Model, sea_orm::DbErr> {
+        let id = Uuid::now_v7();
+        let now = chrono::Utc::now();
+        let model = ai_chat_message::ActiveModel {
+            id: Set(id),
+            tenant_id: Set(params.tenant_id),
+            session_id: Set(params.session_id),
+            role: Set(params.role),
+            content: Set(params.content),
+            tool_calls: Set(params.tool_calls),
+            tool_call_id: Set(params.tool_call_id),
+            token_count: Set(params.token_count),
+            created_at: Set(now),
+            updated_at: Set(now),
+            created_by: Set(Some(params.user_id)),
+            updated_by: Set(Some(params.user_id)),
+            deleted_at: Set(None),
+            version_lock: Set(1),
+        };
+        let result = model.insert(&self.db).await?;
+        Ok(result)
+    }
+
+    pub async fn list_messages(
+        &self,
+        tenant_id: Uuid,
+        session_id: Uuid,
+        limit: u64,
+    ) -> Result<Vec<ai_chat_message::Model>, sea_orm::DbErr> {
+        ai_chat_message::Entity::find()
+            .filter(ai_chat_message::Column::TenantId.eq(tenant_id))
+            .filter(ai_chat_message::Column::SessionId.eq(session_id))
+            .filter(ai_chat_message::Column::DeletedAt.is_null())
+            .order_by_asc(ai_chat_message::Column::CreatedAt)
+            .limit(limit)
+            .all(&self.db)
+            .await
+    }
+
+    pub async fn save_tool_call_log(
+        &self,
+        params: SaveToolCallLogParams,
+    ) -> Result<ai_tool_call_log::Model, sea_orm::DbErr> {
+        let id = Uuid::now_v7();
+        let model = ai_tool_call_log::ActiveModel {
+            id: Set(id),
+            tenant_id: Set(params.tenant_id),
+            session_id: Set(params.session_id),
+            message_id: Set(params.message_id),
+            tool_name: Set(params.tool_name),
+            parameters: Set(params.parameters),
+            result_summary: Set(params.result_summary),
+            execution_ms: Set(Some(params.execution_ms)),
+            success: Set(params.success),
+            created_at: Set(chrono::Utc::now()),
+            created_by: Set(Some(params.user_id)),
+        };
+        let result = model.insert(&self.db).await?;
+        Ok(result)
+    }
+}

crates/erp-ai/src/service/chat_session.rs

@@ -0,0 +1,101 @@
+use sea_orm::{
+    ActiveModelTrait, ColumnTrait, DatabaseConnection, EntityTrait, QueryFilter, QueryOrder, Set,
+};
+use uuid::Uuid;
+
+use crate::entity::ai_chat_session;
+
+pub struct ChatSessionService {
+    db: DatabaseConnection,
+}
+
+impl ChatSessionService {
+    pub fn new(db: DatabaseConnection) -> Self {
+        Self { db }
+    }
+
+    pub async fn create(
+        &self,
+        tenant_id: Uuid,
+        user_id: Uuid,
+        patient_id: Option<Uuid>,
+        title: Option<String>,
+    ) -> Result<ai_chat_session::Model, sea_orm::DbErr> {
+        let id = Uuid::now_v7();
+        let now = chrono::Utc::now();
+        let model = ai_chat_session::ActiveModel {
+            id: Set(id),
+            tenant_id: Set(tenant_id),
+            user_id: Set(user_id),
+            patient_id: Set(patient_id),
+            title: Set(title),
+            status: Set("active".to_string()),
+            metadata: Set(None),
+            created_at: Set(now),
+            updated_at: Set(now),
+            created_by: Set(Some(user_id)),
+            updated_by: Set(Some(user_id)),
+            deleted_at: Set(None),
+            version_lock: Set(1),
+        };
+        let result = model.insert(&self.db).await?;
+        Ok(result)
+    }
+
+    pub async fn list(
+        &self,
+        tenant_id: Uuid,
+        user_id: Uuid,
+    ) -> Result<Vec<ai_chat_session::Model>, sea_orm::DbErr> {
+        ai_chat_session::Entity::find()
+            .filter(ai_chat_session::Column::TenantId.eq(tenant_id))
+            .filter(ai_chat_session::Column::UserId.eq(user_id))
+            .filter(ai_chat_session::Column::DeletedAt.is_null())
+            .filter(ai_chat_session::Column::Status.ne("closed"))
+            .order_by_desc(ai_chat_session::Column::UpdatedAt)
+            .all(&self.db)
+            .await
+    }
+
+    pub async fn get(
+        &self,
+        tenant_id: Uuid,
+        session_id: Uuid,
+    ) -> Result<Option<ai_chat_session::Model>, sea_orm::DbErr> {
+        ai_chat_session::Entity::find()
+            .filter(ai_chat_session::Column::TenantId.eq(tenant_id))
+            .filter(ai_chat_session::Column::Id.eq(session_id))
+            .filter(ai_chat_session::Column::DeletedAt.is_null())
+            .one(&self.db)
+            .await
+    }
+
+    pub async fn close(&self, tenant_id: Uuid, session_id: Uuid) -> Result<bool, sea_orm::DbErr> {
+        let session = self.get(tenant_id, session_id).await?;
+        let Some(session) = session else {
+            return Ok(false);
+        };
+        let mut active: ai_chat_session::ActiveModel = session.into();
+        active.status = Set("closed".to_string());
+        active.updated_at = Set(chrono::Utc::now());
+        active.update(&self.db).await?;
+        Ok(true)
+    }
+
+    pub async fn rename(
+        &self,
+        tenant_id: Uuid,
+        session_id: Uuid,
+        new_title: String,
+    ) -> Result<bool, sea_orm::DbErr> {
+        let session = self.get(tenant_id, session_id).await?;
+        let Some(session) = session else {
+            return Ok(false);
+        };
+        let mut active: ai_chat_session::ActiveModel = session.into();
+        active.title = Set(Some(new_title));
+        active.updated_at = Set(chrono::Utc::now());
+        active.update(&self.db).await?;
+        Ok(true)
+    }
+}

crates/erp-ai/src/service/mod.rs

@@ -2,6 +2,8 @@ pub mod analysis;
 pub mod analysis_queue;
 pub mod auto_analysis;
 pub mod cache;
+pub mod chat_message;
+pub mod chat_session;
 pub mod comparison;
 pub mod cost;
 pub mod dialysis_risk_scorer;

crates/erp-ai/src/state.rs

@@ -7,6 +7,8 @@ use sea_orm::DatabaseConnection;
 use crate::provider::registry::ProviderRegistry;
 use crate::service::analysis::AnalysisService;
 use crate::service::cache::CacheService;
+use crate::service::chat_message::ChatMessageService;
+use crate::service::chat_session::ChatSessionService;
 use crate::service::feature_flag_service::FeatureFlagService;
 use crate::service::insight_service::InsightService;
 use crate::service::knowledge::KnowledgeService;
@@ -32,4 +34,6 @@ pub struct AiState {
     pub insight_service: Arc<InsightService>,
     pub feature_flags: Arc<FeatureFlagService>,
     pub knowledge: Arc<KnowledgeService>,
+    pub chat_session: Arc<ChatSessionService>,
+    pub chat_message: Arc<ChatMessageService>,
 }

crates/erp-server/src/main.rs

@@ -615,6 +615,12 @@ async fn main() -> anyhow::Result<()> {
                     erp_ai::service::embedding::EmbeddingService::from_settings(&db).await,
                 ),
             )),
+            chat_session: std::sync::Arc::new(
+                erp_ai::service::chat_session::ChatSessionService::new(db.clone()),
+            ),
+            chat_message: std::sync::Arc::new(
+                erp_ai::service::chat_message::ChatMessageService::new(db.clone()),
+            ),
         }
     };