adding user authentication

src/application/dtos/file_dto.rs

@@ -61,4 +61,26 @@ impl From<FileDto> for File {
             dto.modified_at
         )
     }
+}
+
+impl FileDto {
+    /// Creates an empty file DTO for stub implementations
+    pub fn empty() -> Self {
+        Self {
+            id: "stub-id".to_string(),
+            name: "stub-file".to_string(),
+            path: "/stub/path".to_string(),
+            size: 0,
+            mime_type: "application/octet-stream".to_string(),
+            folder_id: None,
+            created_at: 0,
+            modified_at: 0,
+        }
+    }
+}
+
+impl Default for FileDto {
+    fn default() -> Self {
+        Self::empty()
+    }
 }

src/application/dtos/folder_dto.rs

@@ -80,4 +80,25 @@ impl From<FolderDto> for Folder {
             dto.modified_at
         )
     }
+}
+
+impl FolderDto {
+    /// Creates an empty folder DTO for stub implementations
+    pub fn empty() -> Self {
+        Self {
+            id: "stub-id".to_string(),
+            name: "stub-folder".to_string(),
+            path: "/stub/path".to_string(),
+            parent_id: None,
+            created_at: 0,
+            modified_at: 0,
+            is_root: true,
+        }
+    }
+}
+
+impl Default for FolderDto {
+    fn default() -> Self {
+        Self::empty()
+    }
 }

src/application/dtos/mod.rs

@@ -2,4 +2,5 @@ pub mod file_dto;
 pub mod folder_dto;
 pub mod i18n_dto;
 pub mod pagination;
+pub mod user_dto;
 

src/application/dtos/user_dto.rs

@@ -0,0 +1,67 @@
+use serde::{Serialize, Deserialize};
+use chrono::{DateTime, Utc};
+use crate::domain::entities::user::{User, UserRole};
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct UserDto {
+    pub id: String,
+    pub username: String,
+    pub email: String,
+    pub role: String,
+    pub storage_quota_bytes: i64,
+    pub storage_used_bytes: i64,
+    pub created_at: DateTime<Utc>,
+    pub updated_at: DateTime<Utc>,
+    pub last_login_at: Option<DateTime<Utc>>,
+    pub active: bool,
+}
+
+impl From<User> for UserDto {
+    fn from(user: User) -> Self {
+        Self {
+            id: user.id().to_string(),
+            username: user.username().to_string(),
+            email: user.email().to_string(),
+            role: format!("{}", user.role()),
+            storage_quota_bytes: user.storage_quota_bytes(),
+            storage_used_bytes: user.storage_used_bytes(),
+            created_at: user.created_at(),
+            updated_at: user.updated_at(),
+            last_login_at: user.last_login_at(),
+            active: user.is_active(),
+        }
+    }
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct LoginDto {
+    pub username: String,
+    pub password: String,
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct RegisterDto {
+    pub username: String,
+    pub email: String,
+    pub password: String,
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct AuthResponseDto {
+    pub user: UserDto,
+    pub access_token: String,
+    pub refresh_token: String,
+    pub token_type: String,
+    pub expires_in: i64,
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct ChangePasswordDto {
+    pub current_password: String,
+    pub new_password: String,
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct RefreshTokenDto {
+    pub refresh_token: String,
+}