Description:
Currently, we don't store information about message reactions in our backups. This task is to add support for message reactions both in the data model and in the UI.

Model:

• Update the MessageData type in api.ts to include a reactions property.
• Update runner.ts to extract and store reactions from Telegram data when backing up messages.

Visualization:

• Update app/dialog/[id]/backup/[cid]/page.tsx to display reactions for each message in the backup view.