perf(bridge): 商品检索改用短关键词并恢复分阶段计时

bridge/test/product-query.test.js

@@ -2,7 +2,7 @@
 
 const test = require('node:test');
 const assert = require('node:assert/strict');
-const { translateProductQuery } = require('../src/product-query');
+const { translateProductQuery, extractProductKeyword } = require('../src/product-query');
 
 test('translateProductQuery: Chinese category alias -> English title', () => {
   const entries = [
@@ -20,3 +20,20 @@ test('translateProductQuery: English query unchanged', () => {
   assert.equal(out.translated, false);
   assert.equal(out.query, 'hoop earrings');
 });
+
+test('extractProductKeyword: drops quantities/currency/transaction words', () => {
+  assert.equal(extractProductKeyword('We need 500 stainless steel rings wholesale under 10 dollars'), 'stainless steel rings');
+  assert.equal(extractProductKeyword('500 rings'), 'rings');
+  assert.equal(extractProductKeyword('do you have gold hoop earrings?'), 'gold hoop earrings');
+  assert.equal(extractProductKeyword('do you accept returns on stainless steel rings'), 'stainless steel rings');
+});
+
+test('extractProductKeyword: caps at 4 tokens, keeps CJK', () => {
+  assert.equal(extractProductKeyword('neo stainless steel rings 500 pcs'), 'neo stainless steel rings');
+  assert.equal(extractProductKeyword('简约不锈钢戒指'), '简约不锈钢戒指');
+});
+
+test('extractProductKeyword: pure quantity/transaction returns empty', () => {
+  assert.equal(extractProductKeyword('500 pcs wholesale'), '');
+  assert.equal(extractProductKeyword(''), '');
+});