finish index feature

tests/nonpartitioned/data/nonpartitioned/TestNonPartitioned_InsertRead/users.jsonl

@@ -0,0 +1,3 @@
+{"email":"a@test.com","id":1,"name":"Alice"}                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
+{"email":"b@test.com","id":2,"name":"Bob"}                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
+{"email":"c@test.com","id":3,"name":"Charlie"}                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 

tests/nonpartitioned/data/nonpartitioned/index_fail/users.jsonl

@@ -0,0 +1 @@
+{"email":"x@test.com","id":1}