fix: 输入校验忽略多个连续空格与大小写；统一中英文引号与空白规范化

kouyu_english/lib/core/seed_courses.dart

@@ -1081,8 +1081,17 @@ const a0SegmentGrammarNotes = <String, String>{
 String grammarNoteForSegment(String segmentId, String lessonId) =>
     a0SegmentGrammarNotes[segmentId] ?? grammarNoteForLesson(lessonId);
 
+String _normalizeDialogueInput(String response) => response
+    .toLowerCase()
+    .replaceAll('\u2019', "'")
+    .replaceAll('\u2018', "'")
+    .replaceAll('’', "'")
+    .replaceAll('‘', "'")
+    .replaceAll(RegExp(r'\s+'), ' ')
+    .trim();
+
 bool matchesSegmentDialogue(String segmentId, int stage, String response) {
-  final text = response.toLowerCase().replaceAll('’', "'");
+  final text = _normalizeDialogueInput(response);
   final segment = a0LessonSegments.values
       .expand((segments) => segments)
       .where((item) => item.id == segmentId)
@@ -1091,7 +1100,7 @@ bool matchesSegmentDialogue(String segmentId, int stage, String response) {
     return false;
   }
   bool hasAny(Iterable<String> terms) =>
-      terms.any((term) => text.contains(term));
+      terms.any((term) => text.contains(_normalizeDialogueInput(term)));
   // A phone-number report needs both the reporting frame and at least one
   // spoken digit. Other segment turns need one reviewed, task-specific term.
   if (segmentId == 'a0-04-c' && stage == 0) {
@@ -1102,7 +1111,7 @@ bool matchesSegmentDialogue(String segmentId, int stage, String response) {
 }
 
 bool matchesSegmentIndependent(String segmentId, String response) {
-  final text = response.toLowerCase().replaceAll('’', "'");
+  final text = _normalizeDialogueInput(response);
   final segment = a0LessonSegments.values
       .expand((segments) => segments)
       .where((item) => item.id == segmentId)
@@ -1110,17 +1119,18 @@ bool matchesSegmentIndependent(String segmentId, String response) {
   if (segment == null) return true;
   if (segmentId == 'a0-04-a' || segmentId == 'a0-04-b') {
     final count = segment.independentRequiredTerms
-        .where((term) => text.contains(term))
+        .where((term) => text.contains(_normalizeDialogueInput(term)))
         .length;
     return count >= 3;
   }
   if (segmentId == 'a0-04-c') {
     return segment.independentRequiredTerms
-            .where((term) => text.contains(term))
+            .where((term) => text.contains(_normalizeDialogueInput(term)))
             .length >=
         3;
   }
-  return segment.independentRequiredTerms.any((term) => text.contains(term));
+  return segment.independentRequiredTerms
+      .any((term) => text.contains(_normalizeDialogueInput(term)));
 }
 
 class LessonDialogue {
@@ -1156,7 +1166,8 @@ bool _containsTerm(String text, String term) {
     return term.split(' + ').every((part) => _containsTerm(text, part.trim()));
   }
   if (term.startsWith('#')) return _matchesStructure(text, term);
-  final escaped = RegExp.escape(term.toLowerCase());
+  final normTerm = _normalizeDialogueInput(term);
+  final escaped = RegExp.escape(normTerm);
   return RegExp('(?<![a-z])$escaped(?![a-z])').hasMatch(text);
 }
 
@@ -1178,9 +1189,6 @@ bool _matchesStructure(String text, String token) => switch (token) {
   _ => false,
 };
 
-String _normalizeDialogueInput(String response) =>
-    response.toLowerCase().replaceAll('\u2019', "'").replaceAll('\u2018', "'");
-
 /// Whole-lesson and free-scene dialogues validate the same way segment
 /// dialogues do: the turn has to contain the language the turn is teaching.
 bool matchesDialogueStage(LessonDialogue script, int stage, String response) {