The provider discovery path is working here; the failure is stale TUI state.

ManualModelEntry is a substate of the model-discovery screen. If the user enters manual model-id mode, backs out to provider selection, and then selects openai again, the probe can succeed and populate DiscoveredModels, but the old ManualModelEntry == true value still causes the page to render the manual textbox instead of the discovered model list.

Resetting these fields at the start of each provider probe makes each probe a fresh model-selection attempt:

ManualModelEntry = false;
SelectedModelId = null;

ManualModelEntry = false ensures the successful probe renders the selectable discovered-model list. SelectedModelId = null clears any stale model ID typed during a previous attempt so the next provider selection cannot carry old input forward.

I verified this with a baseline proof test: the regression failed on unmodified dev because ManualModelEntry remained true after backing out and selecting openai again, even though the probe returned models. The same test passes with this reset in place.