Replace isahc with async ureq (#18414)

REplace isahc with ureq everywhere gpui is used.

This should allow us to make http requests without libssl; and avoid a
long-tail of panics caused by ishac.

Release Notes:

- (potentially breaking change) updated our http client

---------

Co-authored-by: Mikayla <mikayla@zed.dev>

crates/semantic_index/Cargo.toml

@@ -51,7 +51,7 @@ workspace.workspace = true
 worktree.workspace = true
 
 [dev-dependencies]
-isahc_http_client.workspace = true
+ureq_client.workspace = true
 env_logger.workspace = true
 client = { workspace = true, features = ["test-support"] }
 fs = { workspace = true, features = ["test-support"] }

crates/semantic_index/examples/index.rs

@@ -2,7 +2,6 @@ use client::Client;
 use futures::channel::oneshot;
 use gpui::App;
 use http_client::HttpClientWithUrl;
-use isahc_http_client::IsahcHttpClient;
 use language::language_settings::AllLanguageSettings;
 use project::Project;
 use semantic_index::{OpenAiEmbeddingModel, OpenAiEmbeddingProvider, SemanticDb};
@@ -29,7 +28,11 @@ fn main() {
         let clock = Arc::new(FakeSystemClock::default());
 
         let http = Arc::new(HttpClientWithUrl::new(
-            IsahcHttpClient::new(None, None),
+            Arc::new(ureq_client::UreqClient::new(
+                None,
+                "Zed semantic index example".to_string(),
+                cx.background_executor().clone(),
+            )),
             "http://localhost:11434",
             None,
         ));