fix: stop event propagation when removing file in AI chat preview (#18779)

## Summary

When clicking the ✕ button on an uploaded file in the AI chatbot context
preview, the click event bubbled up to the `StyledClickableContainer`
parent, which triggered `handleClick` (opening the file preview modal)
instead of — or in addition to — calling `onRemove`.

**Root cause:** `StyledClickableContainer` has `onClick={handleClick}`
at the div level. The `AvatarOrIcon` (X button) `onClick={onRemove}`
callback didn't stop propagation, so the event continued to bubble and
opened the preview.

**Fix:** Wrap `onRemove` in a `handleRemove` callback that calls
`e.stopPropagation()` before invoking the original handler.

Fixes #18298

---------

Co-authored-by: victorjzq <zhiqiangjia@users.noreply.github.com>
Co-authored-by: Charles Bochet <charles@twenty.com>
Co-authored-by: Charles Bochet <charlesBochet@users.noreply.github.com>

packages/twenty-front/src/modules/ai/components/internal/AgentChatFilePreview.tsx

@@ -72,11 +72,13 @@ export const AgentChatFilePreview = ({
   );
 
   const rightComponent = onRemove ? (
-    <AvatarOrIcon
-      Icon={IconX}
-      IconColor={theme.font.color.secondary}
-      onClick={onRemove}
-    />
+    <div onClick={(e) => e.stopPropagation()}>
+      <AvatarOrIcon
+        Icon={IconX}
+        IconColor={theme.font.color.secondary}
+        onClick={onRemove}
+      />
+    </div>
   ) : undefined;
 
   const hasRightDivider = isDefined(onRemove);