fix: upload failure, share dialog, shared view styling, dark mode fixes

- Fix 'folder_id is required' upload error by adding create_home_folder
  through the full hexagonal architecture (trait, service, repository, auth)
- Fix double upload issue with _isUploading concurrency guard
- Fix Share context menu doing nothing (ID collision between sharedView
  and main share dialog resolved with sv- prefix)
- Fix Compartidos tab duplicate headers and broken layout
- Add missing .shared-dialog CSS with dark mode support
- Fix dark mode white backgrounds on empty-state, shared-filters,
  trash-actions, action-btn, and header
- Fix i18n key mismatches in sharedView
- Bump version to 0.4.1

Closes #120

src/domain/repositories/folder_repository.rs

@@ -99,4 +99,12 @@ pub trait FolderRepository: Send + Sync + 'static {
 
     /// Permanently deletes a folder (used by the trash)
     async fn delete_folder_permanently(&self, folder_id: &str) -> Result<(), DomainError>;
+
+    /// Creates a root-level home folder for a user.
+    /// This is used during user registration to create the user's personal folder.
+    async fn create_home_folder(
+        &self,
+        user_id: &str,
+        name: String,
+    ) -> Result<Folder, DomainError>;
 }