CI: Tighten live smoke tool verification

[F16shen]

Summary

• make live smoke fail fast when a custom API base is paired with a bare model name
• align check-tool-support with the runtime auto tool-calling path instead of probing required mode
• add regression coverage for the verification behavior

Testing

• /home/lixin/workspace/aishell/aish/.venv/bin/python -m pytest tests/test_verification.py tests/live_smoke/conftest.py -q
• /home/lixin/workspace/aishell/aish/.venv/bin/python -m pytest tests/test_provider_registry.py tests/test_cli.py tests/test_verification.py -q
• AISH_LIVE_SMOKE_MODEL=openai/gpt-5.1 AISH_LIVE_SMOKE_API_BASE=http://www.aishell.ai:8080/aitest/v1 AISH_LIVE_SMOKE_API_KEY=*** make test-live-smoke

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