In PR #13229, we introduced the ebucket for HFE.
Before this PR, when updating eitems stored in ebuckets, the lack of
incremental fragmentation support for non-kvstore data structures (until
PR #13814) meant that we had to reverse lookup the position of the eitem
in the ebucket and then perform the update.
This approach was inefficient as it often required frequent traversals
of the segment list to locate and update the item.

To address this issue, in this PR, This PR implements incremental
fragmentation for hash dict ebuckets and server.hexpires.
By incrementally defrag the ebuckets, we also perform defragmentation
for the associated items, eliminates the need for frequent traversals of
the segment list for defragging the eitem.

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Co-authored-by: Moti Cohen <moticless@gmail.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

## Background
1. All hash objects that contain HFE are referenced by db->hexpires.
2. All fields in a dict hash object with HFE are referenced by an
ebucket.

So when we defrag the hash object or the field in a dict with HFE, we
also need to update the references in them.

## Interface
1. Add a new interface `ebDefragItem`, which can accept a defrag
callback to defrag items in ebuckets, and simultaneously update their
references in the ebucket.

## Mainly changes
1. The key type of dict of hash object is no longer sds, so add new
`activeDefragHfieldDict()` to defrag the dict instead of
`activeDefragSdsDict()`.
2. When we defrag the dict of hash object by using `dictScanDefrag()`,
we always set the defrag callback `defragKey` of `dictDefragFunctions`
to NULL, because we can't reallocate a field with out updating it's
reference in ebuckets.
Instead, we will defrag the field of the dict and update its reference
in the callback `dictScanDefrag` of dictScanFunction().
3. When we defrag the hash robj with HFE, we will use `ebDefragItem` to
defrag the robj and update the reference in db->hexpires.

## TODO:
Defrag ebucket structure incremently, which will be handler in a future
PR.

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Co-authored-by: Ozan Tezcan <ozantezcan@gmail.com>
Co-authored-by: Moti Cohen <moti.cohen@redis.com>