language_model: Remove use_any_tool method from LanguageModel (#27930)

This PR removes the `use_any_tool` method from the `LanguageModel`
trait.

It was not being used anywhere, and doesn't really fit in our new tool
use story.

Release Notes:

- N/A

crates/language_models/src/provider/open_ai.rs

@@ -12,9 +12,7 @@ use language_model::{
     LanguageModelName, LanguageModelProvider, LanguageModelProviderId, LanguageModelProviderName,
     LanguageModelProviderState, LanguageModelRequest, RateLimiter, Role,
 };
-use open_ai::{
-    FunctionDefinition, ResponseStreamEvent, ToolChoice, ToolDefinition, stream_completion,
-};
+use open_ai::{ResponseStreamEvent, stream_completion};
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 use settings::{Settings, SettingsStore};
@@ -331,43 +329,6 @@ impl LanguageModel for OpenAiLanguageModel {
         }
         .boxed()
     }
-
-    fn use_any_tool(
-        &self,
-        request: LanguageModelRequest,
-        tool_name: String,
-        tool_description: String,
-        schema: serde_json::Value,
-        cx: &AsyncApp,
-    ) -> BoxFuture<'static, Result<futures::stream::BoxStream<'static, Result<String>>>> {
-        let mut request = into_open_ai(request, self.model.id().into(), self.max_output_tokens());
-        request.tool_choice = Some(ToolChoice::Other(ToolDefinition::Function {
-            function: FunctionDefinition {
-                name: tool_name.clone(),
-                description: None,
-                parameters: None,
-            },
-        }));
-        request.tools = vec![ToolDefinition::Function {
-            function: FunctionDefinition {
-                name: tool_name.clone(),
-                description: Some(tool_description),
-                parameters: Some(schema),
-            },
-        }];
-
-        let response = self.stream_completion(request, cx);
-        self.request_limiter
-            .run(async move {
-                let response = response.await?;
-                Ok(
-                    open_ai::extract_tool_args_from_events(tool_name, Box::pin(response))
-                        .await?
-                        .boxed(),
-                )
-            })
-            .boxed()
-    }
 }
 
 pub fn into_open_ai(