decoder for open vocabulary keyword spotting (#505)

* various fixes to ContextGraph to support open vocabulary keywords decoder

* Add keyword spotter runtime

* Add binary

* First version works

* Minor fixes

* update text2token

* default values

* Add jni for kws

* add kws android project

* Minor fixes

* Remove unused interface

* Minor fixes

* Add workflow

* handle extra info in texts

* Minor fixes

* Add more comments

* Fix ci

* fix cpp style

* Add input box in android demo so that users can specify their keywords

* Fix cpp style

* Fix comments

* Minor fixes

* Minor fixes

* minor fixes

* Minor fixes

* Minor fixes

* Add CI

* Fix code style

* cpplint

* Fix comments

* Fix error

sherpa-onnx/csrc/online-stream.h

@@ -14,9 +14,11 @@
 #include "sherpa-onnx/csrc/online-ctc-decoder.h"
 #include "sherpa-onnx/csrc/online-paraformer-decoder.h"
 #include "sherpa-onnx/csrc/online-transducer-decoder.h"
+#include "sherpa-onnx/csrc/transducer-keyword-decoder.h"
 
 namespace sherpa_onnx {
 
+class TransducerKeywordResult;
 class OnlineStream {
  public:
   explicit OnlineStream(const FeatureExtractorConfig &config = {},
@@ -76,6 +78,9 @@ class OnlineStream {
   void SetResult(const OnlineTransducerDecoderResult &r);
   OnlineTransducerDecoderResult &GetResult();
 
+  void SetKeywordResult(const TransducerKeywordResult &r);
+  TransducerKeywordResult &GetKeywordResult(bool remove_duplicates = false);
+
   void SetCtcResult(const OnlineCtcDecoderResult &r);
   OnlineCtcDecoderResult &GetCtcResult();
 
@@ -92,7 +97,7 @@ class OnlineStream {
    */
   const ContextGraphPtr &GetContextGraph() const;
 
-  // for streaming parformer
+  // for streaming paraformer
   std::vector<float> &GetParaformerFeatCache();
   std::vector<float> &GetParaformerEncoderOutCache();
   std::vector<float> &GetParaformerAlphaCache();