Make get_varset_members return both names and indexes as a convenience, since every downstream function now takes the index

Author: PhilMiller

bmi.sidl

@@ -18,7 +18,7 @@ package csdms version 3.0-alpha1 {
 
     // Variable set information
     int get_varset_member_count(in string set_name, out int count);
-    int get_varset_members(in string set_name, out array<string, 1> names);
+    int get_varset_members(in string set_name, out array<string, 1> names, out array<int, 1> indexes);
 
     // Variable information
     int get_var_index(in string name, out int index);

docs/source/bmi.info_funcs.md

@@ -94,25 +94,25 @@ Gets the number of exchange items in a particular set exposed by the model.
 :sync: sidl
 
 ```java
-int get_varset_members(in string set_name, out array<string, 1> names);
+int get_varset_members(in string set_name, out array<string, 1> names, out array<int, 1> indexes);
 ```
 :::
 :::{tab-item} Python
 :sync: python
 ```python
-def get_varset_members(self, set_name: str) -> tuple[str, ...]:
+def get_varset_members(self, set_name: str) -> Mapping[str, int]:
 ```
 :::
 :::{tab-item} c
 :sync: c
 ```c
-int get_varset_members(void *self, const char *name, char const* const* members);
+int get_varset_members(void *self, const char *name, char const* const* members, int *indexes);
 ```
 :::
 ::::
 
-Gets an array of names for the variables the model publishes in the requested set.
-The length of the array is given by {ref}`get-varset-member-count`.
+Gets the names and indexes for the variables the model publishes in the requested set.
+The length of each array is given by {ref}`get-varset-member-count`.
 The names are preferably in the form of CSDMS {term}`Standard Names`.
 Standard Names enable a modeling framework to determine whether a
 variable in one model is equivalent to, or compatible with,