style: apply cargo fmt to entire codebase

Standardize code formatting across all 173 Rust source files
using rustfmt. No functional changes - purely cosmetic.

This establishes a consistent code style baseline for the
project going forward.

src/application/dtos/trash_dto.rs

@@ -30,4 +30,4 @@ pub struct RestoreFromTrashRequest {
 #[derive(Debug, Deserialize)]
 pub struct DeletePermanentlyRequest {
     pub trash_id: String,
-}
+}