Add C# code snippets to retries documentation (#1587)

Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>
Co-authored-by: Niels Swimberghe <[email protected]>

Author: devin-ai-integration[bot]

fern/products/sdks/guides/retries-with-backoff.mdx

@@ -68,6 +68,34 @@ default retry limit when instantiating the client.
       )
     ```
   </CodeBlock>
+  <CodeBlock title="C#">
+    ```csharp {4}
+    using Imdb;
+
+    var client = new ImdbClient(new ClientOptions {
+      MaxRetries = 1 // overrides the default retry limit to 1
+    });
+    ```
+  </CodeBlock>
+  <CodeBlock title="Swift">
+    ```swift {5}
+    import Imdb
+
+    let client = ImdbClient(
+      baseURL: "https://api.imdb.com",
+      maxRetries: 1 // overrides the default retry limit to 1
+    )
+    ```
+  </CodeBlock>
+  <CodeBlock title="PHP">
+    ```php {4}
+    use Imdb\ImdbClient;
+    
+    $client = new ImdbClient([
+      "maxRetries" => 1 // overrides the default retry limit to 1
+    ]);
+    ```
+  </CodeBlock>
 </CodeBlocks>
 
 It's also possible to override the retry limit on a per-request basis.
@@ -103,5 +131,26 @@ It's also possible to override the retry limit on a per-request basis.
       )
     ```
   </CodeBlock>
+  <CodeBlock title="C#">
+    ```csharp {2}
+      var movie = await client.Movie.GetAsync("tt0111161", new RequestOptions {
+        MaxRetries = 3 // overrides the default retry limit to 3
+      });
+    ```
+  </CodeBlock>
+  <CodeBlock title="Swift">
+    ```swift {2}
+      let movie = try await client.movie.get("tt0111161", requestOptions: RequestOptions(
+        maxRetries: 3 // overrides the default retry limit to 3
+      ))
+    ```
+  </CodeBlock>
+  <CodeBlock title="PHP">
+    ```php {2}
+      $movie = $client->movie->get("tt0111161", [
+        "maxRetries" => 3 // overrides the default retry limit to 3
+      ]);
+    ```
+  </CodeBlock>
 </CodeBlocks>