feat(fileDto, folderDto): add is_favorite + is_shared

- provide is_shared and is_favorite information in DTO, information propagated as badge/buttons per items
      regarding performances I try to be minimalis on SQL to prevent any perf regression

    - remove old set of sharedids and favoriteids (was not functionnal anymore)
    - fix date picker (no past selection) in grant
    - fix contextmenu close on /files section

src/interfaces/api/handlers/webdav_handler.rs

@@ -560,6 +560,9 @@ async fn handle_propfind(
                 category: intern_display("Folder"),
                 created_by: None,
                 updated_by: None,
+                // Synthetic root, not on the SPA path — safe default.
+                is_favorite: false,
+                is_shared: false,
             };
             // Skip the 2-query quota resolution when the request's prop list
             // never mentions quota (benches/QUOTA-PATH.md).