docs: API 레퍼런스 TypeDoc 자동생성 전환 (수기 → 자동)

- packages/docs 에 typedoc + typedoc-plugin-markdown + typedoc-vitepress-theme devDep 추가
- typedoc.json 신설: entry=estreuv/src/index.js(JSDoc 소스), 마크다운을 api/ 로 생성
  - excludeExternals 로 LitElement/DOM 상속 멤버 제외 (EstreUVElement 9499→461줄)
- docs:api 스크립트 추가, prebuild 훅으로 빌드 시 자동 재생성
- .vitepress/config.js: 생성된 api/typedoc-sidebar.json 을 사이드바로 로드 (없을 때 폴백)
- 수기 api/index.md 제거, 생성 산출물 api/ 는 .gitignore 처리 (types/ 와 동일 정책)
- 검증: vitepress build 통과(데드링크 0), estreuv 테스트 39 passed

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: SoliEstre

.gitignore

@@ -12,3 +12,7 @@ packages/*/types/
 *.tsbuildinfo
 .vitepress/cache/
 .vitepress/dist/
+
+# TypeDoc-generated API reference (regenerated by `npm run docs:api`, see packages/docs/typedoc.json)
+# The sidebar (api/typedoc-sidebar.json) lives inside this dir and is covered too.
+packages/docs/api/

package-lock.json

@@ -1,4 +1,17 @@
 import { defineConfig } from 'vitepress';
+import { createRequire } from 'node:module';
+
+// TypeDoc (typedoc-vitepress-theme) writes the API sidebar to
+// `typedoc-sidebar.json` at build time. It is a generated artifact (gitignored),
+// so load it defensively: a fresh checkout has no file until `npm run docs:api`
+// runs (wired into `prebuild`). Fall back to a single link when absent.
+const require = createRequire(import.meta.url);
+let apiSidebar = [{ text: 'API reference', link: '/api/' }];
+try {
+  apiSidebar = require('../api/typedoc-sidebar.json');
+} catch {
+  // not generated yet — keep the fallback
+}
 
 // EstreUV.js — standalone docs site. EstreUV-centric; references EstreUI
 // where the pairing matters. (EstreUI has its own site; EstreUX covers both.)
@@ -76,9 +89,7 @@ export default defineConfig({
           items: [{ text: 'Pairing with EstreUI', link: '/guide/pairing' }],
         },
       ],
-      '/api/': [
-        { text: 'API reference', link: '/api/' },
-      ],
+      '/api/': apiSidebar,
     },
 
     socialLinks: [