Allow extensions to control the redirect policy for the HTTP client (#16162)

This PR extends the extension API with support for controlling the
redirect policy used by the HTTP client.

Release Notes:

- N/A

crates/extension_api/src/extension_api.rs

@@ -21,6 +21,7 @@ pub use wit::{
     },
     zed::extension::http_client::{
         fetch, fetch_stream, HttpMethod, HttpRequest, HttpResponse, HttpResponseStream,
+        RedirectPolicy,
     },
     zed::extension::nodejs::{
         node_binary_path, npm_install_package, npm_package_installed_version,

crates/extension_api/wit/since_v0.1.0/http-client.wit

@@ -5,23 +5,44 @@ interface http-client {
         method: http-method,
         /// The URL to which the request should be made.
         url: string,
-        /// Headers for the request.
+        /// The headers for the request.
         headers: list<tuple<string, string>>,
         /// The request body.
         body: option<list<u8>>,
+        /// The policy to use for redirects.
+        redirect-policy: redirect-policy,
     }
 
     /// HTTP methods.
     enum http-method {
+        /// `GET`
         get,
-        post,
-        put,
-        delete,
+        /// `HEAD`
         head,
+        /// `POST`
+        post,
+        /// `PUT`
+        put,
+        /// `DELETE`
+        delete,
+        /// `OPTIONS`
         options,
+        /// `PATCH`
         patch,
     }
 
+    /// The policy for dealing with redirects received from the server.
+    variant redirect-policy {
+        /// Redirects from the server will not be followed.
+        ///
+        /// This is the default behavior.
+        no-follow,
+        /// Redirects from the server will be followed up to the specified limit.
+        follow-limit(u32),
+        /// All redirects from the server will be followed.
+        follow-all,
+    }
+
     /// An HTTP response.
     record http-response {
         /// The response headers.
@@ -36,7 +57,8 @@ interface http-client {
     /// An HTTP response stream.
     resource http-response-stream {
         /// Retrieves the next chunk of data from the response stream.
-        /// Returns None if the stream has ended.
+        ///
+        /// Returns `Ok(None)` if the stream has ended.
         next-chunk: func() -> result<option<list<u8>>, string>;
     }