feat(server): KB prompt优化、字幕修复、S2S重连、助手配置API

- assistantProfileConfig: KB answer prompt改为分层策略(严格产品信息+灵活常识补充)
- nativeVoiceGateway: S2S upstream自动重连(最多50次)、event 351字幕debounce(800ms取最长文本)
- toolExecutor: 确定性query改写增强、KB查询传递session上下文
- contextKeywordTracker: 支持KB话题记忆优先enrichment
- contentSafeGuard: 新增品牌安全内容过滤服务
- assistantProfileService: 新增助手配置CRUD服务
- routes/assistantProfile: 新增助手配置API路由
- knowledgeKeywords: 扩展KB关键词词典
- fastAsrCorrector: ASR纠错规则更新
- tests/: KB prompt测试、保护窗口测试、Viking性能测试
- docs/: 助手配置API文档、系统提示词目录

test2/server/tests/test_viking_cold_start.js

@@ -0,0 +1,91 @@
+const path = require('path');
+const { performance } = require('perf_hooks');
+
+require('dotenv').config({ path: path.join(__dirname, '../.env') });
+
+const ToolExecutor = require('../services/toolExecutor');
+
+const coldTestQueryTemplates = [
+  { name: 'Product - Q10 Unique', template: 'Q10辅酵素氧修护有什么独特功效 ' },
+  { name: 'Product - IB5 Unique', template: 'IB5口腔免疫喷雾如何正确使用 ' },
+  { name: 'Product - CC胶囊 Unique', template: 'CC胶囊的主要适用人群有哪些 ' },
+  { name: 'Company - 邓白氏 Unique', template: '德国PM邓白氏认证的具体含义是什么 ' },
+  { name: 'Technology - 火炉原理 Unique', template: '请详细阐述一下火炉原理的核心思想 ' }
+];
+
+async function runColdStartTest() {
+  console.log('='.repeat(80));
+  console.log('VIKING COLD START PERFORMANCE TEST');
+  console.log('(No Cache - Real API Calls)');
+  console.log('='.repeat(80));
+  console.log('');
+
+  const allResults = [];
+
+  for (const { name, template } of coldTestQueryTemplates) {
+    console.log(`Testing (Cold): ${name}`);
+    const latencies = [];
+    const hits = [];
+    
+    for (let i = 0; i < 3; i++) {
+      const uniqueQuery = template + Math.random();
+      const start = performance.now();
+      let result;
+      try {
+        result = await ToolExecutor.searchKnowledge({ query: uniqueQuery, response_mode: 'answer' }, []);
+        const latency = performance.now() - start;
+        latencies.push(latency);
+        hits.push(!!result.hit);
+        console.log(`  Attempt ${i + 1}: ${latency.toFixed(2)}ms, hit=${result.hit}, source=${result.source}`);
+      } catch (e) {
+        console.log(`  Attempt ${i + 1} error: ${e.message}`);
+      }
+    }
+
+    if (latencies.length > 0) {
+      const avgLatency = latencies.reduce((a, b) => a + b, 0) / latencies.length;
+      const minLatency = Math.min(...latencies);
+      const maxLatency = Math.max(...latencies);
+      const hitRate = hits.filter(h => h).length / hits.length;
+
+      allResults.push({
+        name,
+        template,
+        avgLatency,
+        minLatency,
+        maxLatency,
+        hitRate,
+        latencies
+      });
+
+      console.log(`  → Avg: ${avgLatency.toFixed(2)}ms, Min: ${minLatency.toFixed(2)}ms, Max: ${maxLatency.toFixed(2)}ms, Hit Rate: ${(hitRate * 100).toFixed(1)}%\n`);
+    }
+  }
+
+  console.log('='.repeat(80));
+  console.log('COLD START SUMMARY');
+  console.log('='.repeat(80));
+  
+  if (allResults.length > 0) {
+    const totalAvg = allResults.reduce((a, b) => a + b.avgLatency, 0) / allResults.length;
+    const totalMin = Math.min(...allResults.flatMap(r => r.latencies));
+    const totalMax = Math.max(...allResults.flatMap(r => r.latencies));
+    const totalHitRate = allResults.reduce((a, b) => a + b.hitRate, 0) / allResults.length;
+
+    console.log(`\nOverall Average Latency: ${totalAvg.toFixed(2)}ms`);
+    console.log(`Overall Min Latency: ${totalMin.toFixed(2)}ms`);
+    console.log(`Overall Max Latency: ${totalMax.toFixed(2)}ms`);
+    console.log(`Overall Hit Rate: ${(totalHitRate * 100).toFixed(1)}%`);
+
+    console.log('\nFastest queries:');
+    allResults.sort((a, b) => a.avgLatency - b.avgLatency).forEach((r, i) => {
+      console.log(`  ${i + 1}. ${r.name}: ${r.avgLatency.toFixed(2)}ms`);
+    });
+  }
+
+  console.log('\n' + '='.repeat(80));
+
+  return allResults;
+}
+
+runColdStartTest().catch(console.error);