Function pull_changes 

pub async unsafe fn pull_changes(
    db: *mut sqlite3,
    storage: &dyn SyncStorage,
    our_device_id: &str,
    cursors: &HashMap<String, u64>,
    library_dir: &LibraryDir,
    blob_plan: &dyn BlobPlan,
) -> Result<(HashMap<String, u64>, PullResult), PullError>

Pull and apply all new changesets from the sync storage.

db is a raw sqlite3 connection pointer. The caller MUST ensure no SyncSession is active – the protocol requires ending the session before pulling to avoid contaminating the next outgoing changeset.

cursors maps device_id -> last_seq we’ve applied from that device.

Returns the updated cursors map and a summary of what was applied.

Safety

db must be a valid, open sqlite3 connection pointer.