chore(ui): 파비콘을 xavis.co.kr favicon.ico와 동일하게 적용

- public/favicon.ico 추가, /favicon.ico 및 partials 링크 갱신
- 인라인 오류 HTML의 icon 링크 정리

Made-with: Cursor

views/partials/favicon.ejs

@@ -1,2 +1,2 @@
-<link rel="icon" href="/public/images/xavis-logo.png" type="image/png" />
-<link rel="apple-touch-icon" href="/public/images/xavis-logo.png" />
+<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+<link rel="apple-touch-icon" href="/favicon.ico" />