Use clickable video thumbnail in README

Co-authored-by: Codex <noreply@openai.com>

Author: Deno2026

README.md

@@ -37,12 +37,10 @@ This is different from ComfyUI Subgraph. Subgraph moves nodes into a child graph
 
 ### `(Deno) Ideogram Director`
 
-[Watch the long-form workflow demo](https://youtu.be/Z8s27skkIDM)
+[![Watch the Ideogram Director workflow demo](https://img.youtube.com/vi/Z8s27skkIDM/maxresdefault.jpg)](https://youtu.be/Z8s27skkIDM)
 
 Visual Ideogram 4 prompt builder for structured JSON captions and bbox layout work.
 
-![Deno Ideogram Director](docs/images/ideogram-director.png)
-
 Main features:
 
 - draw and edit bbox regions directly on the ComfyUI canvas

docs/README.ko.md

@@ -31,12 +31,10 @@ ComfyUI Subgraph는 노드를 하위 그래프로 이동시키는 기능입니
 
 ### `(Deno) Ideogram Director`
 
-[롱폼 워크플로우 소개 영상](https://youtu.be/Z8s27skkIDM)
+[![Ideogram Director workflow demo](https://img.youtube.com/vi/Z8s27skkIDM/maxresdefault.jpg)](https://youtu.be/Z8s27skkIDM)
 
 Ideogram 4용 구조화 JSON 프롬프트와 bbox 배치를 ComfyUI 캔버스 안에서 편집하는 시각형 프롬프트 빌더입니다.
 
-![Deno Ideogram Director](images/ideogram-director.png)
-
 주요 기능:
 
 - 캔버스 위에서 bbox 영역을 직접 그리고 편집