🚀 Feature: Show thumbnail/preview for uploaded image attachments in Chat UI

### 🔖 Feature description

Implement a lightweight image preview component in the frontend:

- In MessageInput: Show a small thumbnail with a "remove" (X) button once an image is successfully uploaded and the attachment ID is retrieved.

- In ConversationBubble: If a message contains an image attachment ID, render a scaled-down preview of the image above or alongside the text response.

### 🎤 Why is this feature needed ?

Currently, when a user uploads an image attachment via the pipeline, there is no visual confirmation or thumbnail preview of the image within the chat bubble or message input state.

### ✌️ How do you aim to achieve this?

.

### 🔄️ Additional Information

_No response_

### 👀 Have you spent some time to check if this feature request has been raised before?

- [x] I checked and didn't find similar issue

### Are you willing to submit PR?

Yes I am willing to submit a PR!

Start by locating the frontend MessageInput and ConversationBubble components and tracing how uploaded image attachment IDs are returned and rendered. Add the thumbnail, image preview, and remove action described in the issue, then verify both the pending-upload state and a conversation message containing an image attachment.

Written by the indexing model from the issue text.