Issue: agtype build map rejects valid AGTYPE keys; age tostring cannot handle unknown-typed inputs

Issue: agtype build map rejects valid AGTYPE keys; age tostring cannot handle unknown-typed inputs: a task in LegoFlow-SWE (Harbor dataset). Current failure with AGTYPE key: sql -- This should succeed but currently raises an error SELECT agtype build map('"agtype key"'::agtype, 42);