Rename regex search tool to grep and accept an include glob pattern (#29100)

This PR renames the `regex_search` tool to `grep` because I think it
conveys more meaning to the model, the idea of searching the filesystem
with a regular expression. It's also one word and the model seems to be
using it effectively after some additional prompt tuning.

It also takes an include pattern to filter on the specific files we try
to search. I'd like to encourage the model to scope its searches more
aggressively, as in my testing, I'm only seeing it filter on file
extension.

Release Notes:

- N/A

crates/gpui/src/app/test_context.rs

@@ -113,7 +113,7 @@ impl AppContext for TestAppContext {
 
 impl TestAppContext {
     /// Creates a new `TestAppContext`. Usually you can rely on `#[gpui::test]` to do this for you.
-    pub fn new(dispatcher: TestDispatcher, fn_name: Option<&'static str>) -> Self {
+    pub fn build(dispatcher: TestDispatcher, fn_name: Option<&'static str>) -> Self {
         let arc_dispatcher = Arc::new(dispatcher.clone());
         let background_executor = BackgroundExecutor::new(arc_dispatcher.clone());
         let foreground_executor = ForegroundExecutor::new(arc_dispatcher);
@@ -146,7 +146,7 @@ impl TestAppContext {
 
     /// returns a new `TestAppContext` re-using the same executors to interleave tasks.
     pub fn new_app(&self) -> TestAppContext {
-        Self::new(self.dispatcher.clone(), self.fn_name)
+        Self::build(self.dispatcher.clone(), self.fn_name)
     }
 
     /// Called by the test helper to end the test.
@@ -178,6 +178,11 @@ impl TestAppContext {
         &self.foreground_executor
     }
 
+    fn new<T: 'static>(&mut self, build_entity: impl FnOnce(&mut Context<T>) -> T) -> Entity<T> {
+        let mut cx = self.app.borrow_mut();
+        cx.new(build_entity)
+    }
+
     /// Gives you an `&mut App` for the duration of the closure
     pub fn update<R>(&self, f: impl FnOnce(&mut App) -> R) -> R {
         let mut cx = self.app.borrow_mut();

crates/gpui/src/text_system/line_wrapper.rs

@@ -329,7 +329,7 @@ mod tests {
 
     fn build_wrapper() -> LineWrapper {
         let dispatcher = TestDispatcher::new(StdRng::seed_from_u64(0));
-        let cx = TestAppContext::new(dispatcher, None);
+        let cx = TestAppContext::build(dispatcher, None);
         let id = cx.text_system().font_id(&font("Zed Plex Mono")).unwrap();
         LineWrapper::new(id, px(16.), cx.text_system().platform_text_system.clone())
     }