Error on attempt to get 'SRU' sgroup name contradicts API documentation

[NadezhdaKatcman]

Summary
Inconsistency between api doc and implementation: attempt to get 'SRU' sgroup name gives error while doc says it should work fine

Steps to Reproduce

1. Create 'SRU' sgroup
2. Get name of created sgroup

Python script to reproduce the issue:
`mol = indigo.createMolecule()
mol.addAtom("C")

query = indigo.createQueryMolecule()
query.addAtom("C")

matcher = indigo.substructureMatcher(mol)
match = matcher.match(query)

if match:
sgroup = mol.createSGroup("SRU", match, "TEST")
print (f"group created: {sgroup.getSGroupName()}")`

Actual behavior
Attempt to get name of the created sgroup throws error:

print (f"grup created: {sgroup.getSGroupName()}")
File "...\Python313\site-packages\indigo\indigo\indigo_object.py", line 1970, in getSGroupName
return IndigoLib.checkResultString(self._lib().indigoGetSGroupName(self.id))
File "...\Python313\site-packages\indigo\indigo\indigo_lib.py", line 1178, in checkResultString
return IndigoLib.checkResultPtr(result, exception_class).decode()
File "...\Python313\site-packages\indigo\indigo\indigo_lib.py", line 1171, in checkResultPtr
raise exception_class(IndigoLib.lib.indigoGetLastError())
indigo.indigo.indigo_exception.IndigoException: core: is not a superatom

Expected behavior
No inconsistency between behavior described in documentation and actual behavior of getSGroupName for 'SRU' sgroups

Environment details:

• indigo: 1.40.0
• python 3.13
• Windows 11 Enterprise. Version 25H2

Attachments
From documentation:

Additional context

• for 'SUP' sgroups getting group name works fine