fix: accept native Fireworks model IDs in doctor

[ft-ioxcs]

Summary

Fixes a false-positive hermes doctor warning for native Fireworks model IDs.

Fireworks model IDs can legitimately use the path-shaped form:

accounts/fireworks/models/qwen3p7-plus

When model.provider is fireworks, this is a native Fireworks model ID, not an OpenRouter-style vendor/model aggregator slug. The current doctor check treats any model string containing / as vendor-prefixed unless the provider is in the aggregator allowlist, so it incorrectly reports:

model.default 'accounts/fireworks/models/qwen3p7-plus' uses a vendor/model slug but provider is 'fireworks'

Change

• Keep the existing vendor-slug warning for native providers.
• Add a narrow exception for Fireworks model IDs matching the native accounts/.../models/... shape.
• Add a regression test covering provider: fireworks with default: accounts/fireworks/models/qwen3p7-plus.

This avoids broadening Fireworks to accept every slash-containing model string. For example, the check can still warn if someone configures an actual two-part aggregator-style model slug on the native Fireworks provider.

Test plan

Confirmed the regression test fails before the fix with the exact false-positive warning.

Then ran:

./venv/bin/python -m pytest tests/hermes_cli/test_doctor.py::test_run_doctor_accepts_native_fireworks_account_model_ids -q

Result:

1 passed, 1 warning

Ran the related provider-slug doctor tests:

./venv/bin/python -m pytest \
  tests/hermes_cli/test_doctor.py::test_run_doctor_accepts_native_fireworks_account_model_ids \
  tests/hermes_cli/test_doctor.py::test_run_doctor_accepts_hermes_provider_ids_that_catalog_aliases \
  -q

Result:

5 passed, 1 warning

Ran the full doctor test module:

./venv/bin/python -m pytest tests/hermes_cli/test_doctor.py -q

Result:

65 passed, 1 warning

Compiled touched Python files:

./venv/bin/python -m py_compile hermes_cli/doctor.py tests/hermes_cli/test_doctor.py

Ran the live doctor command against the local config and confirmed the Fireworks warning no longer appears:

./venv/bin/python -m hermes_cli.main doctor | grep -E "vendor-prefixed|qwen3p7-plus|model.default 'accounts/fireworks|Found [0-9]+ issue" || true

Output only showed the remaining unrelated issue count, with no Fireworks/vendor-prefix warning:

Found 1 issue(s) to address:

[teknium1]

Fireworks AI support landed via PR #62593. This contribution was part of the Fireworks provider cluster credited in the salvage PR; thank you for the implementation and review work.