feat: instant tag suggestions, persistent disk cache, history limit settings, match highlighting and category badges (v2.0.9)

lib/backend/models/tag_suggestion.dart

@@ -22,6 +22,30 @@ class TagSuggestion {
   final String providerId;
 
   String get categoryLabel => category.name;
+
+  Map<String, dynamic> toJson() => {
+        'name': name,
+        'category': category.name,
+        'postCount': postCount,
+        'providerId': providerId,
+      };
+
+  factory TagSuggestion.fromJson(Map<String, dynamic> json) => TagSuggestion(
+        name: (json['name'] ?? '').toString(),
+        category: tagCategoryFromString((json['category'] ?? '').toString()),
+        postCount: (json['postCount'] as num?)?.toInt() ?? 0,
+        providerId: (json['providerId'] ?? '').toString(),
+      );
+
+  @override
+  bool operator ==(Object other) =>
+      identical(this, other) ||
+      other is TagSuggestion &&
+          runtimeType == other.runtimeType &&
+          name.toLowerCase() == other.name.toLowerCase();
+
+  @override
+  int get hashCode => name.toLowerCase().hashCode;
 }
 
 TagCategory tagCategoryFromString(String? value) {