feat: implement heal subsystem for automatic data repair

- Add heal module with core types (HealType, HealRequest, HealTask)
- Implement HealManager for task scheduling and execution
- Add HealStorageAPI trait and ECStoreHealStorage implementation
- Integrate heal capabilities into scanner for automatic repair
- Support multiple heal types: object, bucket, disk, metadata, MRF, EC decode
- Add progress tracking and event system for heal operations
- Merge heal and scanner error types for unified error handling
- Include comprehensive logging and metrics for heal operations

Signed-off-by: junxiang Mu <1948535941@qq.com>

crates/ahm/src/lib.rs

@@ -16,6 +16,7 @@ use std::sync::OnceLock;
 use tokio_util::sync::CancellationToken;
 
 pub mod error;
+pub mod heal;
 pub mod scanner;
 
 pub use error::{Error, Result};
@@ -23,6 +24,7 @@ pub use scanner::{
     BucketTargetUsageInfo, BucketUsageInfo, DataUsageInfo, Scanner, ScannerMetrics, load_data_usage_from_backend,
     store_data_usage_in_backend,
 };
+pub use heal::{HealManager, HealRequest, HealType, HealOptions, HealPriority};
 
 // Global cancellation token for AHM services (scanner and other background tasks)
 static GLOBAL_AHM_SERVICES_CANCEL_TOKEN: OnceLock<CancellationToken> = OnceLock::new();