ruby : extend API (#2551)

* Handle objs in Ruby code

* Add task to make Makefile

* Share commont constance in test suites

* Add model-related APIs

* Add Whisper::Model class

* Add tests for Whisper::Model

* Add missing LDFLAG -lstdc++

* Add tests for Whisper.log_set

* Add Whisper.set_log

* Define log level

* Add document on logging

* Add license section to README

* Add document on Whisper::Model

* Fix examples in README

* Add test for Model with GC

* Make dependency on Makefile more accurate

* Fix bug about Whisper::Model and GC

bindings/ruby/tests/test_model.rb

@@ -0,0 +1,44 @@
+require_relative "helper"
+
+class TestModel < TestBase
+  def test_model
+    whisper = Whisper::Context.new(MODEL)
+    assert_instance_of Whisper::Model, whisper.model
+  end
+
+  def test_attributes
+    whisper = Whisper::Context.new(MODEL)
+    model = whisper.model
+
+    assert_equal 51864, model.n_vocab
+    assert_equal 1500, model.n_audio_ctx
+    assert_equal 512, model.n_audio_state
+    assert_equal 8, model.n_audio_head
+    assert_equal 6, model.n_audio_layer
+    assert_equal 448, model.n_text_ctx
+    assert_equal 512, model.n_text_state
+    assert_equal 8, model.n_text_head
+    assert_equal 6, model.n_text_layer
+    assert_equal 80, model.n_mels
+    assert_equal 1, model.ftype
+    assert_equal "base", model.type
+  end
+
+  def test_gc
+    model = Whisper::Context.new(MODEL).model
+    GC.start
+
+    assert_equal 51864, model.n_vocab
+    assert_equal 1500, model.n_audio_ctx
+    assert_equal 512, model.n_audio_state
+    assert_equal 8, model.n_audio_head
+    assert_equal 6, model.n_audio_layer
+    assert_equal 448, model.n_text_ctx
+    assert_equal 512, model.n_text_state
+    assert_equal 8, model.n_text_head
+    assert_equal 6, model.n_text_layer
+    assert_equal 80, model.n_mels
+    assert_equal 1, model.ftype
+    assert_equal "base", model.type
+  end
+end