MultiCombobox: Bugs

### What happened? When width is auto, options overflow the container and it is impossible to interact with the component: https://codesandbox.io/p/devbox/react-fiddle-forked-85s93h?workspaceId=ws_72q8MnBFyHoeDCUfzQ8VPk https://github.com/user-attachments/assets/6f9427b1-2136-4b18-a3eb-feb642a29818 When width is hardcoded, collapsed options cannot be removed: https://codesandbox.io/p/devbox/react-fiddle-forked-ngf7zq?workspaceId=ws_72q8MnBFyHoeDCUfzQ8VPk https://github.com/user-attachments/assets/7cc086aa-0ce0-407f-8f8e-77e2f65e8021 ### What did you expect to happen? MultiCombobox would not break when the options exceed the max width. MultiCombobox would allow removing collapsed options when expanded. ### Did this work before? N/A ### How do we reproduce it? When width is auto, options overflow the container and it is impossible to interact with the component: https://codesandbox.io/p/devbox/react-fiddle-forked-85s93h?workspaceId=ws_72q8MnBFyHoeDCUfzQ8VPk When width is hardcoded, collapsed options cannot be removed: https://codesandbox.io/p/devbox/react-fiddle-forked-ngf7zq?workspaceId=ws_72q8MnBFyHoeDCUfzQ8VPk ### Is the bug inside a dashboard panel? N/A ### Environment (with versions)? N/A ### Grafana platform? None ### Datasource(s)? N/A