fix: resolve all clippy warnings and convert integration_tests to custom cfg

- Add type aliases (FileRow, FolderRow, FolderRowPaginated, FolderRowOptUser) to reduce type complexity
- Simplify redundant closures in app_password_handler and webdav_handler
- Remove needless borrow in auth_handler
- Collapse nested if/let chains in login_lockout, webdav_lock, auth, rate_limit
- Box LockEntry in acquire() Err variant to fix large enum variant warning
- Rename DeviceCodeStatus::from_str to parse to avoid should_implement_trait lint
- Add #[allow(clippy::too_many_arguments)] and #[allow(clippy::result_unit_err)] where appropriate
- Convert integration_tests from cargo feature to custom cfg attribute
- Add check-cfg lint config in Cargo.toml for integration_tests cfg

src/application/services/storage_usage_service.rs

@@ -1,11 +1,11 @@
 use crate::application::ports::auth_ports::UserStoragePort;
 use crate::application::ports::storage_ports::StorageUsagePort;
 use crate::common::errors::DomainError;
+use crate::infrastructure::repositories::pg::UserPgRepository;
 use sqlx::PgPool;
 use std::sync::Arc;
 use tokio::task;
 use tracing::{debug, error, info};
-use crate::infrastructure::repositories::pg::UserPgRepository;
 
 /**
  * Service for managing and updating user storage usage statistics.