Support non-streaming zipformer CTC ASR models (#2340)

This PR adds support for non-streaming Zipformer CTC ASR models across 
multiple language bindings, WebAssembly, examples, and CI workflows.

- Introduces a new OfflineZipformerCtcModelConfig in C/C++, Python, Swift, Java, Kotlin, Go, Dart, Pascal, and C# APIs
- Updates initialization, freeing, and recognition logic to include Zipformer CTC in WASM and Node.js
- Adds example scripts and CI steps for downloading, building, and running Zipformer CTC models

Model doc is available at
https://k2-fsa.github.io/sherpa/onnx/pretrained_models/offline-ctc/icefall/zipformer.html

flutter/sherpa_onnx/lib/src/sherpa_onnx_bindings.dart

@@ -266,6 +266,10 @@ final class SherpaOnnxOfflineDolphinModelConfig extends Struct {
   external Pointer<Utf8> model;
 }
 
+final class SherpaOnnxOfflineZipformerCtcModelConfig extends Struct {
+  external Pointer<Utf8> model;
+}
+
 final class SherpaOnnxOfflineWhisperModelConfig extends Struct {
   external Pointer<Utf8> encoder;
   external Pointer<Utf8> decoder;
@@ -333,6 +337,7 @@ final class SherpaOnnxOfflineModelConfig extends Struct {
   external SherpaOnnxOfflineMoonshineModelConfig moonshine;
   external SherpaOnnxOfflineFireRedAsrModelConfig fireRedAsr;
   external SherpaOnnxOfflineDolphinModelConfig dolphin;
+  external SherpaOnnxOfflineZipformerCtcModelConfig zipformerCtc;
 }
 
 final class SherpaOnnxOfflineRecognizerConfig extends Struct {