bip52: Update to Closed

[murchandamus]

This proposal appears abandoned, as it has not had any updates in over four years, and cursory search did not produce any public discussions of it since it was published either.

cc: @pkvk

[jonatack]

Concept ACK

Here are the relevant BIP 3 sections on this:

Closed

A BIP that is of historical interest only, and is not being actively worked on,
promoted or in active use, should be marked as Closed. The reason for moving the
proposal to (or from) Closed should be recorded in the Changelog section in the
same commit that updates the status.

Draft ↦ Closed

BIP authors may decide on their own to change their BIP’s status from Draft to Closed.
If a Draft BIP stops making progress, sees accumulated feedback unaddressed, or
otherwise appears stalled for a year, anyone may propose the BIP status be updated to
Closed. The BIP is then updated to Closed unless the authors assert that they intend to
continue work within four weeks of being contacted.

[murchandamus]

I have emailed Michael and Bogdan to provide them notice of this pull request. In absence of a response, this Status update may proceed after 2026-06-18.

• A Changelog to record the Close reason must be added then, before this PR is merged.

Update: The email to the addresses in the BIP resulted in a delivery failure. I then emailed the Bitcoin Dev mailing list instead.

[danielabrozzoni]

Concept ACK!