agent: Allow customizing temperature by provider/model (#30033)

Adds a new `agent.model_parameters` setting that allows the user to
specify a custom temperature for a provider AND/OR model:

```json5
    "model_parameters": [
      // To set parameters for all requests to OpenAI models:
      {
        "provider": "openai",
        "temperature": 0.5
      },
      // To set parameters for all requests in general:
      {
        "temperature": 0
      },
      // To set parameters for a specific provider and model:
      {
        "provider": "zed.dev",
        "model": "claude-3-7-sonnet-latest",
        "temperature": 1.0
      }
    ],
```

Release Notes:

- agent: Allow customizing temperature by provider/model

---------

Co-authored-by: Max Brunsfeld <maxbrunsfeld@gmail.com>
Co-authored-by: Marshall Bowers <git@maxdeviant.com>

crates/project/src/lsp_store.rs

@@ -3530,7 +3530,7 @@ impl LspStore {
             )
             .detach();
         } else {
-            log::info!("No extension events global found. Skipping JSON schema auto-reload setup");
+            log::debug!("No extension events global found. Skipping JSON schema auto-reload setup");
         }
         cx.observe_global::<SettingsStore>(Self::on_settings_changed)
             .detach();