- Batch Gmail API calls using `googleapis-batcher` for folder processing
- Add concurrency limit for Microsoft Graph folder processing
- Skip IMAP folder sync when no new messages (checks UIDVALIDITY/MODSEQ)
- Refactored `syncMessageFolders` to return folder state directly,
avoiding extra DB round-trips
- Refactored `processPendingFolderActions` to reuse state instead of
querying DB again
- Add unique index on message folders entity
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Co-authored-by: Charles Bochet <charles@twenty.com>
neo773