Merge pull request #473 from EdouardVanbelle/fix/nextcloud+webdav

fix(nextcloud+webdav) fix bugs found via end to end tests

src/application/ports/file_ports.rs

@@ -255,11 +255,17 @@ pub trait FileManagementUseCase: Send + Sync + 'static {
     ) -> Result<FileDto, DomainError>;
 
     /// Copies a file, enforcing that `caller_id` is the owner.
+    ///
+    /// `new_name`, when `Some(_)`, becomes the copy's filename — without it
+    /// the copy keeps the source's name, which makes "same folder, different
+    /// name" copies (classic WebDAV `COPY /a.txt → /b.txt`) collide on the
+    /// `(folder, name, user)` unique index.
     async fn copy_file_with_perms(
         &self,
         file_id: &str,
         caller_id: Uuid,
         target_folder_id: Option<String>,
+        new_name: Option<String>,
     ) -> Result<FileDto, DomainError>;
 
     /// Renames a file, enforcing that `caller_id` is the owner.

src/application/ports/storage_ports.rs

@@ -314,10 +314,16 @@ pub trait FileWritePort: Send + Sync + 'static {
     ///
     /// With blob-dedup, this only creates a new metadata row and increments
     /// the blob reference count — zero disk I/O for the content.
+    ///
+    /// `new_name` is honored when `Some(_)` — without it, copying a file to
+    /// the same folder always collides on the source's filename. WebDAV
+    /// COPY uses this for the "same folder, different name" case (the
+    /// classic `COPY /a.txt → /b.txt` pattern).
     async fn copy_file(
         &self,
         file_id: &str,
         target_folder_id: Option<String>,
+        new_name: Option<&str>,
     ) -> Result<File, DomainError>;
 
     /// Copies an entire folder subtree atomically using ltree.