api: Add createSavedSnippet route

Signed-off-by: Zixuan James Li <[email protected]>

Author: PIG208

Diff for: lib/api/route/saved_snippets.dart

@@ -0,0 +1,12 @@
+import '../core.dart';
+
+/// https://zulip.com/api/create-saved-snippet
+Future<void> createSavedSnippet(ApiConnection connection, {
+  required String title,
+  required String content,
+}) {
+  return connection.post('createSavedSnippet', (_) {}, 'saved_snippets', {
+    'title': RawParameter(title),
+    'content': RawParameter(content),
+  });
+}