feat(session): 实现 Session CRUD 管理功能

backend/internal/api/contract/session.go

@@ -0,0 +1,25 @@
+package contract
+
+import "context"
+
+// SessionService 定义会话服务接口
+type SessionService interface {
+	// Session CRUD
+	CreateSession(ctx context.Context, req *CreateSessionRequest) (*Session, error)
+	GetSession(ctx context.Context, id uint, sessionID string) (*Session, error)
+	UpdateSession(ctx context.Context, id uint, req *UpdateSessionRequest) (*Session, error)
+	DeleteSession(ctx context.Context, id uint) error
+	ListSessions(ctx context.Context, req *ListSessionsRequest) (*SessionList, error)
+
+	// Lifecycle management
+	ActivateSession(ctx context.Context, id uint) error
+	PauseSession(ctx context.Context, id uint) error
+	EndSession(ctx context.Context, id uint) error
+	ResumeSession(ctx context.Context, id uint) error
+
+	// Message management
+	AddMessage(ctx context.Context, sessionID uint, req *AddMessageRequest) (*SessionMessage, error)
+	GetSessionMessages(ctx context.Context, sessionID uint, page, perPage int) (*MessageList, error)
+	DeleteMessage(ctx context.Context, messageID uint) error
+	ClearSessionMessages(ctx context.Context, sessionID uint) error
+}

backend/internal/api/contract/session_type.go

@@ -0,0 +1,99 @@
+package contract
+
+import (
+	"time"
+
+	"github.com/insmtx/SingerOS/backend/types"
+)
+
+// CreateSessionRequest 创建会话请求
+type CreateSessionRequest struct {
+	SessionID     string                       `json:"session_id,omitempty"`
+	Type          string                       `json:"type" binding:"required"`
+	UserID        uint                         `json:"user_id,omitempty"`
+	AssistantID   uint                         `json:"assistant_id,omitempty"`
+	AssistantCode string                       `json:"assistant_code,omitempty"`
+	Title         string                       `json:"title,omitempty"`
+	Metadata      *types.SessionMetadata       `json:"metadata,omitempty"`
+	ExpiredAt     *time.Time                   `json:"expired_at,omitempty"`
+}
+
+// UpdateSessionRequest 更新会话请求
+type UpdateSessionRequest struct {
+	Title         string                       `json:"title,omitempty"`
+	Metadata      *types.SessionMetadata       `json:"metadata,omitempty"`
+	ExpiredAt     *time.Time                   `json:"expired_at,omitempty"`
+}
+
+// ListSessionsRequest 查询会话列表请求
+type ListSessionsRequest struct {
+	Type          *string `form:"type,omitempty"`
+	Status        *string `form:"status,omitempty"`
+	UserID        *uint   `form:"user_id,omitempty"`
+	AssistantID   *uint   `form:"assistant_id,omitempty"`
+	AssistantCode *string `form:"assistant_code,omitempty"`
+	Keyword       *string `form:"keyword,omitempty"`
+	Page          int     `form:"page,default=1"`
+	PerPage       int     `form:"per_page,default=20"`
+}
+
+// AddMessageRequest 添加消息请求
+type AddMessageRequest struct {
+	Role        string                     `json:"role" binding:"required"`
+	Content     string                     `json:"content" binding:"required"`
+	MessageType string                     `json:"message_type,omitempty"`
+	Status      string                     `json:"status,omitempty"`
+	Chunks      []string                   `json:"chunks,omitempty"`
+	Thinking    string                     `json:"thinking,omitempty"`
+	ToolCalls   []types.ToolCall           `json:"tool_calls,omitempty"`
+	Metadata    *types.MessageMetadata     `json:"metadata,omitempty"`
+}
+
+// Session 会话响应结构（对应前端的 Conversation）
+type Session struct {
+	ID            uint                      `json:"id"`
+	SessionID     string                    `json:"session_id"`
+	Type          string                    `json:"type"`
+	UserID        uint                      `json:"user_id"`
+	AssistantID   uint                      `json:"assistant_id"`
+	AssistantCode string                    `json:"assistant_code"`
+	Status        string                    `json:"status"`
+	Title         string                    `json:"title"`
+	Metadata      *types.SessionMetadata    `json:"metadata,omitempty"`
+	MessageCount  int                       `json:"message_count"`
+	LastMessageAt *time.Time                `json:"last_message_at,omitempty"`
+	ExpiredAt     *time.Time                `json:"expired_at,omitempty"`
+	CreatedAt     time.Time                 `json:"created_at"`
+	UpdatedAt     time.Time                 `json:"updated_at"`
+}
+
+// SessionMessage 消息响应结构（对齐前端 Message 模型）
+type SessionMessage struct {
+	ID          string                    `json:"id"`                 // 前端用 string
+	SessionID   string                    `json:"conversation_id"`    // 对应前端的 conversationId
+	Role        string                    `json:"role"`
+	Content     string                    `json:"content"`
+	Chunks      []string                  `json:"chunks,omitempty"`   // 流式片段
+	Status      string                    `json:"status"`             // sending/streaming/complete/error
+	Timestamp   int64                     `json:"timestamp"`          // Unix 毫秒时间戳
+	ToolCalls   []types.ToolCall          `json:"tool_calls,omitempty"`
+	Thinking    string                    `json:"thinking,omitempty"` // 思维链
+	MessageType string                    `json:"message_type,omitempty"`
+	Metadata    *types.MessageMetadata    `json:"metadata,omitempty"`
+	Sequence    int64                     `json:"sequence"`
+	CreatedAt   time.Time                 `json:"created_at"`
+}
+
+// SessionList 会话列表响应
+type SessionList struct {
+	Total int64     `json:"total"`
+	Page  int       `json:"page"`
+	Items []Session `json:"items"`
+}
+
+// MessageList 消息列表响应
+type MessageList struct {
+	Total int64            `json:"total"`
+	Page  int              `json:"page"`
+	Items []SessionMessage `json:"items"`
+}

backend/internal/api/dto/session.go

@@ -0,0 +1 @@
+package dto