feat(divination): 重构手动起卦教程，支持三硬币交互选择

apps/lib/features/divination/data/models/divination_result.dart

@@ -11,6 +11,7 @@ class DivinationResultData {
     required this.lowerName,
     required this.signType,
     required this.keywords,
+    required this.focusPoints,
     required this.conclusion,
     required this.analysis,
     required this.suggestion,
@@ -29,6 +30,7 @@ class DivinationResultData {
   final String lowerName;
   final String signType;
   final String keywords;
+  final List<String> focusPoints;
   final String conclusion;
   final String analysis;
   final String suggestion;
@@ -50,6 +52,7 @@ class DivinationResultData {
       'lowerName': lowerName,
       'signType': signType,
       'keywords': keywords,
+      'focusPoints': focusPoints,
       'conclusion': conclusion,
       'analysis': analysis,
       'suggestion': suggestion,
@@ -86,6 +89,7 @@ class DivinationResultData {
       lowerName: _requiredString(json, 'lowerName'),
       signType: _requiredString(json, 'signType'),
       keywords: _requiredString(json, 'keywords'),
+      focusPoints: _requiredStringList(json, 'focusPoints'),
       conclusion: _requiredString(json, 'conclusion'),
       analysis: _requiredString(json, 'analysis'),
       suggestion: _requiredString(json, 'suggestion'),
@@ -113,6 +117,21 @@ class DivinationResultData {
   }
 }
 
+List<String> _requiredStringList(Map<String, dynamic> json, String key) {
+  final raw = json[key];
+  if (raw is! List<dynamic>) {
+    throw FormatException('Invalid $key payload');
+  }
+  return raw
+      .map((item) {
+        if (item is! String) {
+          throw FormatException('Invalid $key item payload');
+        }
+        return item;
+      })
+      .toList(growable: false);
+}
+
 class GanzhiData {
   const GanzhiData({
     required this.yearGanZhi,