feat: add models for physical files, policies, and user management

- Implement PhysicalFile model to manage physical file references and reference counting.
- Create Policy model with associated options and group links for storage policies.
- Introduce Redeem and Report models for handling redeem codes and reports.
- Add Settings model for site configuration and user settings management.
- Develop Share model for sharing objects with unique codes and associated metadata.
- Implement SourceLink model for managing download links associated with objects.
- Create StoragePack model for managing user storage packages.
- Add Tag model for user-defined tags with manual and automatic types.
- Implement Task model for managing background tasks with status tracking.
- Develop User model with comprehensive user management features including authentication.
- Introduce UserAuthn model for managing WebAuthn credentials.
- Create WebDAV model for managing WebDAV accounts associated with users.

sqlmodels/share.py

@@ -0,0 +1,220 @@
+
+from typing import TYPE_CHECKING
+from datetime import datetime
+from uuid import UUID
+
+from sqlmodel import Field, Relationship, text, UniqueConstraint, Index
+
+from .base import SQLModelBase
+from .mixin import TableBaseMixin
+
+if TYPE_CHECKING:
+    from .user import User
+    from .report import Report
+    from .object import Object
+
+
+# ==================== Base 模型 ====================
+
+class ShareBase(SQLModelBase):
+    """分享基础字段，供 DTO 和数据库模型共享"""
+
+    object_id: UUID
+    """关联的对象UUID"""
+
+    password: str | None = None
+    """分享密码"""
+
+    expires: datetime | None = None
+    """过期时间（NULL为永不过期）"""
+
+    remain_downloads: int | None = None
+    """剩余下载次数（NULL为不限制）"""
+
+    preview_enabled: bool = True
+    """是否允许预览"""
+
+    score: int = 0
+    """兑换此分享所需的积分"""
+
+
+# ==================== 数据库模型 ====================
+
+class Share(SQLModelBase, TableBaseMixin):
+    """分享模型"""
+
+    __table_args__ = (
+        UniqueConstraint("code", name="uq_share_code"),
+        Index("ix_share_source_name", "source_name"),
+        Index("ix_share_user_created", "user_id", "created_at"),
+        Index("ix_share_object", "object_id"),
+    )
+
+    code: str = Field(max_length=64, nullable=False, index=True)
+    """分享码"""
+
+    password: str | None = Field(default=None, max_length=255)
+    """分享密码（加密后）"""
+
+    object_id: UUID = Field(
+        foreign_key="object.id",
+        index=True,
+        ondelete="CASCADE"
+    )
+    """关联的对象UUID"""
+
+    views: int = Field(default=0, sa_column_kwargs={"server_default": "0"})
+    """浏览次数"""
+
+    downloads: int = Field(default=0, sa_column_kwargs={"server_default": "0"})
+    """下载次数"""
+
+    remain_downloads: int | None = Field(default=None)
+    """剩余下载次数 (NULL为不限制)"""
+
+    expires: datetime | None = Field(default=None)
+    """过期时间 (NULL为永不过期)"""
+
+    preview_enabled: bool = Field(default=True, sa_column_kwargs={"server_default": text("true")})
+    """是否允许预览"""
+
+    source_name: str | None = Field(default=None, max_length=255)
+    """源名称（冗余字段，便于展示）"""
+
+    score: int = Field(default=0, sa_column_kwargs={"server_default": "0"})
+    """兑换此分享所需的积分"""
+
+    # 外键
+    user_id: UUID = Field(
+        foreign_key="user.id",
+        index=True,
+        ondelete="CASCADE"
+    )
+    """创建分享的用户UUID"""
+
+    # 关系
+    user: "User" = Relationship(back_populates="shares")
+    """分享创建者"""
+
+    object: "Object" = Relationship(back_populates="shares")
+    """关联的对象"""
+
+    reports: list["Report"] = Relationship(
+        back_populates="share",
+        sa_relationship_kwargs={"cascade": "all, delete-orphan"}
+    )
+    """举报列表"""
+
+    @property
+    def is_dir(self) -> bool:
+        """是否为目录分享（向后兼容属性）"""
+        from .object import ObjectType
+        return self.object.type == ObjectType.FOLDER if self.object else False
+
+
+# ==================== DTO 模型 ====================
+
+class ShareCreateRequest(ShareBase):
+    """创建分享请求 DTO，继承 ShareBase 中的所有字段"""
+    pass
+
+
+class ShareResponse(SQLModelBase):
+    """分享响应 DTO"""
+
+    id: int
+    """分享ID"""
+
+    code: str
+    """分享码"""
+
+    object_id: UUID
+    """关联对象UUID"""
+
+    source_name: str | None
+    """源名称"""
+
+    views: int
+    """浏览次数"""
+
+    downloads: int
+    """下载次数"""
+
+    remain_downloads: int | None
+    """剩余下载次数"""
+
+    expires: datetime | None
+    """过期时间"""
+
+    preview_enabled: bool
+    """是否允许预览"""
+
+    score: int
+    """积分"""
+
+    created_at: datetime
+    """创建时间"""
+
+    is_expired: bool
+    """是否已过期"""
+
+    has_password: bool
+    """是否有密码"""
+
+
+class ShareListItemBase(SQLModelBase):
+    """分享列表项基础字段"""
+
+    id: int
+    """分享ID"""
+
+    code: str
+    """分享码"""
+
+    views: int
+    """浏览次数"""
+
+    downloads: int
+    """下载次数"""
+
+    remain_downloads: int | None
+    """剩余下载次数"""
+
+    expires: datetime | None
+    """过期时间"""
+
+    preview_enabled: bool
+    """是否允许预览"""
+
+    score: int
+    """积分"""
+
+    user_id: UUID
+    """用户UUID"""
+
+    created_at: datetime
+    """创建时间"""
+
+
+class AdminShareListItem(ShareListItemBase):
+    """管理员分享列表项 DTO，添加关联字段"""
+
+    username: str | None
+    """用户名"""
+
+    object_name: str | None
+    """对象名称"""
+
+    @classmethod
+    def from_share(
+        cls,
+        share: "Share",
+        user: "User | None",
+        obj: "Object | None",
+    ) -> "AdminShareListItem":
+        """从 Share ORM 对象构建"""
+        return cls(
+            **ShareListItemBase.model_validate(share, from_attributes=True).model_dump(),
+            username=user.email if user else None,
+            object_name=obj.name if obj else None,
+        )