test: PR30测试 — 子序列匹配、单位系统、volume优先级 + 拼音补字

新增12个测试: pinyinMatchScore、产品名拼音、单位映射、volume优先级
更新2个旧测试适配substring/subsequence匹配
补全拼音: 面、湿

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/__tests__/newFeatures.test.js

@@ -58,15 +58,15 @@ describe('getPinyinInitials', () => {
 })
 
 describe('matchesPinyinInitials', () => {
-  it('matches prefix only', () => {
+  it('matches prefix', () => {
     expect(matchesPinyinInitials('生姜', 's')).toBe(true)
     expect(matchesPinyinInitials('生姜', 'sj')).toBe(true)
-    expect(matchesPinyinInitials('茶树', 's')).toBe(false) // cs doesn't start with s
     expect(matchesPinyinInitials('茶树', 'cs')).toBe(true)
   })
 
-  it('does not match substring', () => {
-    expect(matchesPinyinInitials('茶树', 's')).toBe(false)
+  it('matches substring and subsequence', () => {
+    expect(matchesPinyinInitials('茶树', 's')).toBe(true) // substring
+    expect(matchesPinyinInitials('新瑞活力身体紧致霜', 'js')).toBe(true) // subsequence
   })
 
   it('matches 忍冬花 with r', () => {