feat: 删除亲情卡分类并优化搜索功能

- 移除亲情卡支出分类（前端+后端）
- 搜索结果添加点击编辑功能
- 提取 RecordModal 组件复用（index.js/search.js）
- 添加 useMemo 优化计算性能
- 优化类别查找为 O(1) 映射
- 添加删除分类接口输入验证

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/styles/globals.css

@@ -954,7 +954,9 @@ textarea:focus-visible {
 }
 
 .confirm-card__actions .btn {
-  flex: 1 1 180px;
+  flex: 0 1 auto;
+  min-width: 100px;
+  min-height: 40px;
 }
 
 .error-msg {
@@ -1375,6 +1377,60 @@ textarea:focus-visible {
   color: var(--text-secondary);
 }
 
+/* Simplified Settings */
+.settings-list {
+  display: flex;
+  flex-direction: column;
+  gap: 12px;
+  margin-bottom: 16px;
+}
+
+.settings-link {
+  display: flex;
+  align-items: center;
+  gap: 14px;
+  width: 100%;
+  padding: 16px;
+  background: var(--surface-raised);
+  border: 1px solid rgba(148, 163, 184, 0.12);
+  border-radius: 16px;
+  cursor: pointer;
+  font-size: 0.95rem;
+  color: var(--text-primary);
+  transition: transform var(--transition), box-shadow var(--transition);
+  text-align: left;
+}
+
+.settings-link:hover:not(:disabled) {
+  transform: translateY(-1px);
+  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
+}
+
+.settings-link:active:not(:disabled) {
+  transform: translateY(0);
+}
+
+.settings-link:disabled {
+  opacity: 0.5;
+  cursor: not-allowed;
+}
+
+.settings-link .chevron {
+  margin-left: auto;
+  color: var(--text-tertiary);
+}
+
+.settings-link--danger {
+  color: var(--expense);
+}
+
+.settings-footer {
+  text-align: center;
+  padding: 20px;
+  color: var(--text-tertiary);
+  font-size: 0.85rem;
+}
+
 .about-info p:first-child {
   color: var(--text);
   font-weight: 700;