feat: implement S3 block cleanup on file/space deletion

[marcolaux]

• Implemented DeleteMany in s3store using batch deletion
• Updated index service to return removed CIDs on FileUnbind and SpaceDelete
• Updated deletion log to delete blocks from store when spaces are removed
• Updated file node to delete blocks from store when files are deleted
• Updated CID entry to remove key from Redis when refs count drops to zero

[github-actions]

CLA Assistant Lite bot:
Thank you for your pull request, we really appreciate it!

Please sign our Contributor License Agreement before we can accept your contribution.
You can sign the CLA by simply commenting on this pull request with the following text.

---

I have read the CLA Document and I hereby sign the CLA

---

Marco Laux seems not to be a GitHub user. You need a GitHub account to be able to sign the CLA. If you have already a GitHub account, please add the email address used for this commit to your account.
_{You can retrigger this bot by commenting recheck in this Pull Request}

[marcolaux]

I hereby grant Any Association and its successors or assignees permission to use, copy, modify, distribute, and sub-license my contributions on any terms they like, under all my rights in my contributions. A contribution includes anything I submit to the project. I am giving them this license in order to make it possible for them to accept my contributions into their project.

As far as the law allows, my contributions come as is, without any warranty or condition, and I will not be liable to anyone for any damages related to this software or this license, under any kind of legal claim.