Added test and exposed list_models.

[EricApgar]

Description

Exposed list_models() functionality to list supported models.

Summary of Changes

• Exposed new namespace.
• Added test for list_models.

Proof it Works

configfile: pyproject.toml
testpaths: tests
collected 6 items                                                                                                                                                                              

tests/test_embed.py s          [ 16%]
tests/test_gpt_oss_20b.py s          [ 33%]
tests/test_list_models.py ...          [ 83%]
tests/test_phi4_multimodal_instruct.py s          [100%]

=============== 3 passed, 3 skipped in 1.75s ===============