A compressed-tensors checkpoint that only quantizes the KV cache
(`kv_cache_scheme` set, no `config_groups`) crashed at load time:
`get_experts_scheme` indexed `groups[0]` on an empty list from
`serialized_names` and `get_load_operations`. Guard both on empty
config groups, like the existing sparsity-only case, and add a CI
test on inference-optimization/TinyQwen3-KV-Cache-Only that checks
the scales load onto every attention module.
Kyle Sayers
455c9a0491