Fix tokenizer annotations for explanatory contrast ending (#33)

src/core/services/tokenizer/annotation-stage.test.ts

@@ -246,6 +246,18 @@ test('shouldExcludeTokenFromSubtitleAnnotations excludes explanatory pondering e
   assert.equal(shouldExcludeTokenFromSubtitleAnnotations(token), true);
 });
 
+test('shouldExcludeTokenFromSubtitleAnnotations excludes explanatory contrast endings', () => {
+  const token = makeToken({
+    surface: 'んですけど',
+    headword: 'ん',
+    reading: 'ンデスケド',
+    pos1: '名詞|助動詞|助詞',
+    pos2: '非自立',
+  });
+
+  assert.equal(shouldExcludeTokenFromSubtitleAnnotations(token), true);
+});
+
 test('shouldExcludeTokenFromSubtitleAnnotations excludes auxiliary-stem そうだ grammar tails', () => {
   const token = makeToken({
     surface: 'そうだ',

src/core/services/tokenizer/annotation-stage.ts

@@ -46,6 +46,7 @@ const SUBTITLE_ANNOTATION_EXCLUDED_EXPLANATORY_ENDING_TRAILING_PARTICLES = [
   'ね',
   'よ',
   'な',
+  'けど',
   'よね',
   'かな',
   'かね',

src/core/services/tokenizer/subtitle-annotation-filter.ts

@@ -41,6 +41,7 @@ const SUBTITLE_ANNOTATION_EXCLUDED_EXPLANATORY_ENDING_TRAILING_PARTICLES = [
   'ね',
   'よ',
   'な',
+  'けど',
   'よね',
   'かな',
   'かね',