fix(model): require confirmation for expensive model selections

Rebased onto current main and re-ported across the restructured
surfaces: model flows now thread confirm_provider/base_url/api_key
through hermes_cli/model_setup_flows.py, the Discord picker lives in
plugins/platforms/discord/adapter.py, and the web dashboard picker
applies chat-mode switches via config.set so the expensive-model
confirmation can ride the response.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

hermes_cli/main.py

@@ -3269,6 +3269,7 @@ def _aux_flow_provider_model(
             model_list,
             current_model=current_model,
             pricing=pricing,
+            confirm_provider=provider_slug,
         )
         if selected is None:
             print("No change.")