refactor(topics): 멀티 에이전트용 지식 재편 — _Common(공통 기본기) + Domain_* 구조

에이전트 8종(대화형/프로그래머 C·S/디자이너/설계자/기획자/QA/PD/PM)에게
[공통 기본 능력 + 롤별 Specialty] 2층으로 지식을 주입하기 위한 재분류.
문서 내용·포맷은 무수정, 폴더 이동만 (6,372개 문서 수 보존 확인).

- Topic_Programming → Domain_Programming (내부 구조 보존)
- Topic_Graphic → Domain_Design
- Topic_Business → Domain_Product
- Topic_General → Domain_General
- _Common 신설: Math(구 Topic_Math_Specialty), Reasoning(구 General/From_Thinking & Reasoning),
  Reasoning_Creativity(구 General/From_창의성), Communication(Poetic_Blog_Writing + From_writing)
- 타 도메인의 From_* 폴더는 유지 (출처 표기일 뿐, 이미 도메인에 맞게 분류된 문서)
- 빈 폴더 정리 (memory/procedures)
- 에이전트→폴더 매핑은 workspace의 .astra/agent-knowledge-map.json (9개 에이전트)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

10_Wiki/Topics/Domain_Programming/AI_and_ML/Time to Interactive (TTI).md

@@ -0,0 +1,166 @@
+---
+id: wiki-2026-0508-time-to-interactive-tti
+title: Time to Interactive (TTI)
+category: 10_Wiki/Topics
+status: verified
+canonical_id: self
+aliases: [TTI, Time-to-Interactive]
+duplicate_of: none
+source_trust_level: A
+confidence_score: 0.85
+verification_status: applied
+tags: [web-vitals, performance, frontend, metric]
+raw_sources: []
+last_reinforced: 2026-05-10
+github_commit: pending
+tech_stack:
+  language: javascript
+  framework: lighthouse-web-vitals
+---
+
+# Time to Interactive (TTI)
+
+## 매 한 줄
+> **"매 page가 user input에 reliably 반응할 수 있는 시점"**. 2018 Lighthouse에 도입된 TTI는 main thread quiet window를 측정. 2024년 INP (Interaction to Next Paint) 가 Core Web Vitals 의 official replacement 가 되었지만, TTI는 lab-time diagnostic 으로 여전히 유용.
+
+## 매 핵심
+
+### 매 정의 (Lighthouse algorithm)
+- **First Contentful Paint** 이후 시작.
+- 5-second quiet window: long task (>50ms) 가 없는 구간.
+- network: 동시 in-flight request ≤ 2.
+- 매 quiet window 의 시작 시점 = TTI.
+
+### 매 vs other metrics
+| Metric | Measures | Status (2026) |
+|---|---|---|
+| **FCP** | First Contentful Paint | active |
+| **LCP** | Largest Contentful Paint | Core Web Vital |
+| **TTI** | Main thread quiet | lab only |
+| **TBT** | Total Blocking Time | lab proxy for TTI |
+| **INP** | Interaction → Next Paint | Core Web Vital (2024+ replaces FID) |
+
+### 매 왜 INP가 TTI를 대체했는가
+- TTI 는 lab-only, single point — real user의 interaction 반영 X.
+- INP 는 75th percentile of all interactions — full session 반영.
+- TTI는 여전히 lab regression detection 에 유용.
+
+### 매 응용
+1. CI performance budget (Lighthouse score).
+2. Pre-launch regression detection.
+3. JS bundle size impact 측정.
+
+## 💻 패턴
+
+### Pattern 1: Lighthouse CLI 측정
+```bash
+npx lighthouse https://example.com \
+  --only-categories=performance \
+  --output=json \
+  --chrome-flags="--headless" \
+  --output-path=./report.json
+
+jq '.audits["interactive"].numericValue' report.json
+```
+
+### Pattern 2: Web Vitals JS (real user, INP)
+```javascript
+import { onINP, onLCP, onCLS } from 'web-vitals/attribution';
+
+onINP((metric) => {
+  navigator.sendBeacon('/analytics', JSON.stringify({
+    name: 'INP',
+    value: metric.value,
+    rating: metric.rating,
+    target: metric.attribution?.interactionTarget,
+  }));
+});
+```
+
+### Pattern 3: Reduce TTI — code splitting (React)
+```javascript
+import { lazy, Suspense } from 'react';
+
+const HeavyChart = lazy(() => import('./HeavyChart'));
+
+export function Dashboard() {
+  return (
+    <Suspense fallback={<Skeleton />}>
+      <HeavyChart />
+    </Suspense>
+  );
+}
+```
+
+### Pattern 4: Defer non-critical scripts
+```html
+<!-- Critical: render-blocking ok -->
+<script src="/critical.js"></script>
+
+<!-- Non-critical: defer until after parse -->
+<script src="/analytics.js" defer></script>
+
+<!-- Independent: async -->
+<script src="/ads.js" async></script>
+```
+
+### Pattern 5: Long task observer
+```javascript
+const observer = new PerformanceObserver((list) => {
+  list.getEntries().forEach((entry) => {
+    if (entry.duration > 50) {
+      console.warn('Long task', entry.name, entry.duration);
+      // breakup with scheduler.yield() (2026 baseline)
+    }
+  });
+});
+observer.observe({ entryTypes: ['longtask'] });
+```
+
+### Pattern 6: scheduler.yield (2026)
+```javascript
+async function processItems(items) {
+  for (const item of items) {
+    process(item);
+    if (navigator.scheduling?.isInputPending()) {
+      await scheduler.yield();  // yield to user input
+    }
+  }
+}
+```
+
+## 매 결정 기준
+| 상황 | 매 metric |
+|---|---|
+| RUM (production users) | INP + LCP |
+| Lab regression in CI | TTI / TBT |
+| Initial render speed | FCP / LCP |
+| Layout stability | CLS |
+
+**기본값**: INP + LCP for RUM, TBT for lab CI gates.
+
+## 🔗 Graph
+- 부모: [[Web Performance]] · [[Core Web Vitals Optimization (INP, LCP, CLS)|Core Web Vitals]]
+- 변형: [[INP]] · [[LCP]] · [[TBT]] · [[FID]]
+- 응용: [[Lighthouse]] · [[Code Splitting]]
+- Adjacent: [[Service Worker]] · [[React Server Components — 경계 의식]]
+
+## 🤖 LLM 활용
+**언제**: lab performance regression, JS bundle audit, frontend optimization.
+**언제 X**: production user-facing metric (use INP instead).
+
+## ❌ 안티패턴
+- **TTI as RUM metric**: TTI 는 lab-only. real user 측정에 사용 X.
+- **Optimizing for TTI alone**: LCP / CLS / INP 의 무시.
+- **Synchronous third-party scripts**: ads, analytics 의 sync 로딩 → TTI 폭발.
+- **Hydration-only SPA**: massive JS bundle → bad TTI. Use SSR + Islands / RSC.
+
+## 🧪 검증 / 중복
+- Verified (web.dev/tti, Lighthouse v12, Chrome DevRel 2024 INP migration guide).
+- 신뢰도 A.
+
+## 🕓 Changelog
+| 날짜 | 변경 |
+|---|---|
+| 2026-05-08 | Phase 1 |
+| 2026-05-10 | Manual cleanup — TTI definition + INP migration context |