Allow renaming (relabelling) postage batches

[slapec93]

Summary

Postage batches have an optional label property which can be set at the time of purchase, but it is not on-chain, only saved locally in Bee's database as metadata. The only purpose of label is to attach a tag to the postage batch so that users remember what they purchased them for. For example, I have a postage batch specifically for long-duration static_websites, a different one for mutable testing, and so on.

Motivation

There are cases when I want to re-label them, which is currently not possible:

• I forgot to set a label in the first place
• I no longer use it for its original purpose / want to use for a different reason, and I want to update the label to reflect this
• I set the label correctly but purchased with the wrong parameters (e.g. I wanted mutable_test but accidentally made it immutable), then I want to throw away the mutable_test label and create a new postage batch with the correct parameters
• When the Bee node database is corrupted / nuked, and postage batches are re-synced, they all reset to the "recovered" label

Implementation

This should be a fairly easy (🤞) implementation in Bee with a new endpoint: PATCH /stamps/:batchId accepting a {"label":string} body (or PUT /stamps/:batchId/label).

Drawbacks

AI Disclosure

• This issue contains suggestions and text generated by an LLM.
• I have reviewed the AI generated content thoroughly.
• I possess the technical expertise to responsibly review the AI generated content mentioned in this issue.