acp: Add more logs to model selector to diagnose issue (#36997)

Release Notes:

- N/A

---------

Co-authored-by: Antonio Scandurra <me@as-cii.com>
Co-authored-by: Cole Miller <cole@zed.dev>
Co-authored-by: Joseph T. Lyons <JosephTLyons@gmail.com>
Co-authored-by: Katie Geer <katie@zed.dev>

crates/language_model/src/registry.rs

@@ -208,6 +208,7 @@ impl LanguageModelRegistry {
     ) -> impl Iterator<Item = Arc<dyn LanguageModel>> + 'a {
         self.providers
             .values()
+            .filter(|provider| provider.is_authenticated(cx))
             .flat_map(|provider| provider.provided_models(cx))
     }