crossProviderCandidatesForTest method
The deduped (provider, modelId) pair list the picker is built
from. Exposed for tests so cross-provider invariants (catalog
fallback chains, dedup with the saved entry's modelId) can be
asserted without driving the TUI two-step picker.
Implementation
@visibleForTesting
List<(String, String)> crossProviderCandidatesForTest([String filter = '']) =>
_crossProviderCandidates(filter);