Replace the flawed join-based comparison (entryKeys.join(',')) with
JSON.stringify() to properly handle keys containing commas. The previous
implementation could produce false equality when different key sets
shared the same comma-separated representation (e.g., 'a,b' key vs
separate 'a' and 'b' keys).
This ensures the effect fires correctly when keys change, fixing silent
failures to update derived state.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>