* make more coherent lifecycles
* remove specific implementation on different handlers (they do not need to know existence of ThumbnailSerice nor AudioMetadataService)
* reduce risk of orphean objects
* ensure additional services are correctly wired (ex: Thumbnail generation was not covering all upload cases)
* more details on docs/architecture/file-and-blob-lifecycle.md :
```rust
// application/ports/file_lifecycle.rs
pub trait FileLifecycleHook {
fn on_file_created(file_id, blob_hash, content_type, is_new_blob);
fn on_file_updated(file_id, blob_hash, content_type);
fn on_file_copied(file_id, blob_hash, content_type, source_id)
fn on_file_deleted(file_id);
}
// application/ports/blob_lifecycle.rs
pub trait BlobLifecycleHook {
fn on_blob_created(blob_hash, content_type);
fn on_blob_deleted(blob_hash);
}
```
- Move all sync I/O (id3::Tag, mp3_duration) into spawn_blocking via
extract_metadata_blocking() to avoid stalling Tokio worker threads
- Replace fetch_all with streaming .fetch() in reextract_all_audio_metadata
for O(1) memory usage regardless of audio file count
- Consolidate get_duration_secs into extract_metadata_blocking, eliminating
redundant file open (tag was read twice before)
Edouard Vanbelle