Support array notation for nested keys to avoid dot-splitting conflicts

Support array notation for nested keys to avoid dot-splitting conflicts: a task in LegoFlow-SWE (Harbor dataset). Symptom Keys that contain literal dots (e.g., http://www.w3.org/1999/02/22-rdf-syntax-ns type ) are incorrectly treated as dot-separated nested paths by Fuse. When a user includes such…

The task

**Symptom** Keys that contain literal dots (e.g., `http://www.w3.org/1999/02/22-rdf-syntax-ns#type`) are incorrectly treated as dot-separated nested paths by Fuse. When a user includes such a key in the `keys` option, the dot-notation path splits the name into separate segments, causing the search to fail.

Part of Lego-X/LegoFlow-SWE.