Closes#815.
Three root causes fixed:
1. Provider aliases (z.ai/x.ai/google/grok/claude/aws-bedrock/dashscope/~25 more) not
normalized before _PROVIDER_MODELS lookup — provider fell to empty else-branch while
TUI worked (it normalizes at startup). Fixed via _resolve_provider_alias() + inlined
_PROVIDER_ALIASES table in api/config.py.
2. Silent ImportError in original normalization: 'from hermes_cli.models import
_PROVIDER_ALIASES' inside try/except silently failed without hermes-agent on sys.path
(CI, minimal installs). The inlined table fixes this — normalization now works
regardless of whether hermes-agent is installed.
3. /api/models/live?provider=custom now falls back to custom_providers entries from
config.yaml when provider_model_ids() returns empty.
Also: provider_id on every group in /api/models response for deterministic JS optgroup
matching (no substring false positives). 17 targeted tests, 1725/1725 full suite.