feat: 词汇库搜索、筛选与编辑 (#12)

- GET /api/v1/terms 列表：查询键白名单、page/limit 边界（默认 20、上限 100）、
  排序 updated_at DESC；搜索同时匹配身份键、显示原文与个人释义，转小写后比较（term 为
  二进制排序规则），%/_/\ 按字面值转义；status 与 kind 可组合
- PATCH /api/v1/terms/:id 编辑：复用释义/例句与状态/等级校验，身份不可编辑；
  只有状态或等级变化才重排复习时间，历史作答记录与计数保留
- 学习端新增 /vocab 路由与导航、stores/vocabulary.ts、VocabView.vue（搜索、筛选、
  分页、空态与无结果清除、编辑对话框含 1～7 等级选择器、筛选与页码写入 URL）
- 释义/例句/状态/等级抽成 TermFormFields.vue，与阅读器面板共用，避免规则漂移
- Wiki 记录 Architecture、Business-Rules、Local-Development 与需求更新

learner/src/style.css

@@ -134,6 +134,22 @@ a.chapter-name:hover { color: #315c43; text-decoration: underline; }
 .lookup-saved { color: #2f6b45; font-size: 14px; margin: 12px 0 0; }
 .lookup-actions { display: flex; gap: 8px; margin-top: 14px; flex-wrap: wrap; }
 .review-page { max-width: 680px; }
+.vocab-page { max-width: 760px; }
+.vocab-search { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; margin-top: 22px; }
+.vocab-search label { font-size: 14px; }
+.vocab-search .el-input { max-width: 260px; }
+.vocab-filter { width: 140px; }
+.vocab-list { list-style: none; padding: 0; margin: 18px 0 0; }
+.vocab-row { display: flex; align-items: center; gap: 14px; padding: 14px 16px; margin-bottom: 10px; border: 1px solid #dfe3d6; border-radius: 10px; background: #fffdf8; }
+.vocab-info { min-width: 0; flex: 1; }
+.vocab-term { margin: 0; font-family: Georgia, serif; font-size: 18px; overflow-wrap: anywhere; }
+.vocab-paging { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-top: 18px; }
+.term-fields label { display: flex; justify-content: space-between; gap: 10px; font-size: 14px; margin-top: 14px; }
+.term-fields label span { color: #8b794e; font-size: 12px; }
+.term-fields .el-textarea { margin-top: 8px; }
+.term-fields .el-radio-group { margin-top: 8px; flex-wrap: wrap; gap: 4px 12px; }
+.term-level { display: flex; align-items: center; gap: 10px; margin: 12px 0 0; font-size: 14px; }
+.term-level-select { width: 120px; }
 .chapter-notice { margin: 12px 0 0; padding: 10px 14px; border: 1px solid #d9decf; border-radius: 8px; background: #fbf7ee; color: #6b5b3e; }
 .chapter-list .chapter-row { flex-wrap: wrap; }
 .review-notice { margin: 10px 0 0; padding: 10px 14px; border: 1px solid #d9decf; border-radius: 8px; background: #fbf7ee; color: #6b5b3e; }