feat(ios): extend swipe actions to milestones

crates/app/src/api.rs

@@ -148,6 +148,32 @@ pub async fn save_milestone(
         .map_err(message)
 }
 
+pub async fn set_milestone_closed(
+    server: &Server,
+    owner: &str,
+    repository: &str,
+    id: i64,
+    closed: bool,
+) -> Result<(), String> {
+    client(server)?
+        .set_milestone_closed(&scope(owner, repository)?, id, closed)
+        .await
+        .map(|_| ())
+        .map_err(message)
+}
+
+pub async fn delete_milestone(
+    server: &Server,
+    owner: &str,
+    repository: &str,
+    id: i64,
+) -> Result<(), String> {
+    client(server)?
+        .delete_milestone(&scope(owner, repository)?, &id.to_string())
+        .await
+        .map_err(message)
+}
+
 pub async fn load_pulls(
     server: &Server,
     status: &str,