Fixes - https://github.com/twentyhq/twenty/issues/15263
- Replaced `useLoadSelectedRecordsInContextStore` with
`useLoadMergeRecords` in `useOpenMergeRecordsPageInCommandMenu` for
improved functionality.
- Updated `useMergePreview`, `useMergeRecordsActions`, and
`useMergeRecordsSettings` to utilize `mergeRecordsState` instead of the
deprecated context store hook.
- Cleaned up imports and ensured consistency across merge-related hooks.
https://github.com/user-attachments/assets/453539c9-7f2b-4e8c-bfa1-3ceebca07081
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Co-authored-by: Charles Bochet <charles@twenty.com>