pub fn parse_model_selector_legacy_aware(spec: &str) -> Option<SessionLlmConfig>Expand description
Parse a legacy-aware selector string into a session override.
Supported formats:
"provider:model"→ provider + model"provider"(if it matches a known provider) → provider-only- anything else → model-only (delegates to
session_llm_config_from_cli_model_arg)
Returns None for empty / whitespace-only input.