fix:add tmq_position() interface & optimize commit logic

include/util/taoserror.h

@@ -778,6 +778,7 @@ int32_t* taosGetErrno();
 #define TSDB_CODE_TMQ_VERSION_OUT_OF_RANGE       TAOS_DEF_ERROR_CODE(0, 0x4007)
 #define TSDB_CODE_TMQ_INVALID_VGID               TAOS_DEF_ERROR_CODE(0, 0x4008)
 #define TSDB_CODE_TMQ_INVALID_TOPIC              TAOS_DEF_ERROR_CODE(0, 0x4009)
+#define TSDB_CODE_TMQ_NEED_INITIALIZED           TAOS_DEF_ERROR_CODE(0, 0x4010)
 
 // stream
 #define TSDB_CODE_STREAM_TASK_NOT_EXIST          TAOS_DEF_ERROR_CODE(0, 0x4100)

source/util/src/terror.c

@@ -631,6 +631,7 @@ TAOS_DEFINE_ERROR(TSDB_CODE_SCALAR_CONVERT_ERROR,           "Cannot convert to s
 
 //tmq
 TAOS_DEFINE_ERROR(TSDB_CODE_TMQ_INVALID_MSG,                "Invalid message")
+TAOS_DEFINE_ERROR(TSDB_CODE_TMQ_NEED_INITIALIZED,           "Assignment or poll interface need to be called first")
 TAOS_DEFINE_ERROR(TSDB_CODE_TMQ_SNAPSHOT_ERROR,             "Can not operate in snapshot mode")
 TAOS_DEFINE_ERROR(TSDB_CODE_TMQ_VERSION_OUT_OF_RANGE,       "Offset out of range")
 TAOS_DEFINE_ERROR(TSDB_CODE_TMQ_INVALID_VGID,               "VgId does not belong to this consumer")