perf: findings 6.1, 6.2, 2.6 — async Argon2, moka cache, full streaming migration

- 6.1: PasswordHasherPort now async_trait with spawn_blocking for Argon2
- 6.2: OIDC pending maps migrated from std::sync::Mutex to moka::sync::Cache with TTL
- 2.6: All file download paths migrated to 64KB streaming (get_file_stream / read_blob_stream)
  - WOPI, dedup, batch ZIP, file_retrieval_service consumers migrated
  - WebDAV COPY uses zero-copy dedup (copy_file)
  - Removed dead code: get_file_content, get_file_mmap, read_blob, read_blob_bytes
    from traits, impls, stubs, and mocks (18 files touched)

src/application/dtos/user_dto.rs

@@ -2,7 +2,7 @@ use crate::domain::entities::user::User;
 use chrono::{DateTime, Utc};
 use serde::{Deserialize, Serialize};
 
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct UserDto {
     pub id: String,
     pub username: String,
@@ -49,7 +49,7 @@ pub struct RegisterDto {
     pub role: Option<String>,
 }
 
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct AuthResponseDto {
     pub user: UserDto,
     pub access_token: String,