multi: add labels for static addresses

[GustavoStingelin]

Adds local labels for static addresses. Stacked on #1139 (multi-address-core).

• loop static new --label labels a new receive address, and loop static updatelabel changes or clears a label.
• Labels are stored in LoopDB. They are never sent to the server and are not part of the address script.
• loop static listunspent shows each UTXO's address_label. Deposits in the deposit, withdrawal and loop-in listings show address_label and funding_tx_label, the lnd label of the funding transaction.
• Change addresses created by withdrawals and loop-ins inherit the labels of the deposits they spend. Distinct labels are joined with , up to the 500-character limit.
• Also fixes the shared --label help text: adds a missing space, and gives listswaps its own help, since there the flag is a filter.

ListStaticAddresses, for finding labeled addresses that haven't been funded yet, will come in a follow-up PR.

[gemini-code-assist]

Caution

The consumer version of Gemini Code Assist on GitHub has been sunset. All code review activity has officially ceased.

[starius]

I propose to include the current state of #1139 into this PR, so own label commits go after @hieblmi's commits. Add a note to the PR description not to review the multi-address commits.

I attempted to do a rebase using AI, here is my attempt: https://github.com/starius/loop/commits/staticaddr-combined/ It is not functional.

Some semantic rebase is needed. For example:

• PR 1178 adds 000022_static_address_label, while PR 1139 already uses migrations 22–24 for multi-address persistence.
• PR 1178 assigns protobuf field 2 in NewStaticAddressRequest to label; PR 1139 assigns field 2 to send_coins.
• PR 1178 assigns protobuf field 3 in NewStaticAddressResponse to label; PR 1139 assigns field 3 to send_coins_response.

Found some issues in that multi-address + labels branch that I got:

• the multi-address manager returns an internal *Parameters pointer after releasing its lock, while label update mutates that same object. go test -race reports a real concurrent read/write race. repro
• after multi-address is applied, static new returns a derived receive address, but static summary still reads the legacy/root seed. The two commands no longer describe the same address. repro
• every generated change address is stored with an empty label, regardless of the labels on the consumed deposits. I think labels should be inherited by change - that is a common practice among wallets
• testing gap: the SQL tests read the label back through the same open database/store instance. They do not close and reopen the database or rebuild the manager cache.
• CLI: the shared --label help text says "label for this swap" and lacks a space, while static deposit --label labels the lnd funding transaction and static new --label labels the address.
• ListUnspentDeposits includes the label, but historical deposit/list responses carry the address without the corresponding label - needs unification

Some of them will be resolved by a proper rebase, but some seem genuine.

[GustavoStingelin]

Okay, if we agree to rebase this on top of #1139, I’d prefer to wait until @hieblmi has finished it and its CI is green. This should avoid premature conflicts and duplicated work from having to address #1139’s current race failures in the combined branch.

[GustavoStingelin]

just rebased from master

[GustavoStingelin]

@hieblmi rebased this on multi-address-core (thanks!). The rebase raised two design questions I'd like to settle before we go further:

1. How should address labels relate to funding transaction labels?
2. Should we add a ListStaticAddresses RPC?

[hieblmi]

Thanks @GustavoStingelin

1. How should address labels relate to funding transaction labels?

I think it is valuable to the user to show these together with the funding outpoitns. The loop s listdeposits in multi-address shows something like

{
  "filtered_deposits": [
    {
      "id": "ea6abb…53e71",
      "state": "DEPOSITED",
      "outpoint": "188f55…561be:0",
      "value": "2500000",
      "confirmation_height": "131",
      "blocks_until_expiry": "14395",
      "swap_hash": "",
      "static_address": "bcrt1p…addressA"
    },
    {
      "id": "ab1234…789ef",
      "state": "DEPOSITED",
      "outpoint": "992abc…456de:1",
      "value": "1000000",
      "confirmation_height": "135",
      "blocks_until_expiry": "14399",
      "swap_hash": "",
      "static_address": "bcrt1p…addressB"
    }
  ]
}

We can then add the fields per entry:

"static_address": "bcrt1p…addressA",
"address_label": "Treasury",
"funding_tx_label": "September top-up"

What do you think?

Should we add a ListStaticAddresses RPC?

Is the intention to find addresses with labels, especially if they don't show up in listdeposits?
I think we can do that, and have it paged since this can result in a huge list. And filter for labelled addresses for example.

[GustavoStingelin]

We can then add the fields per entry

Sounds good 👍

Is the intention to find addresses with labels, especially if they don't show up in listdeposits?

Yes. The main case is a user who generates a few receive addresses but hasn't funded them yet. loop static new always derives a fresh address, so those unfunded addresses don't appear in listunspent/listdeposits. If the user didn't save them elsewhere, they're effectively lost and unused addresses keep piling up. A ListStaticAddresses RPC would let users find their addresses again by label, whether or not they've been funded.

To keep this PR focused on labels, I'll add ListStaticAddresses in a follow-up PR.

[litbot-9000]

@hieblmi: review reminder

[GustavoStingelin]

• Deposits in the deposit, withdrawal and loop-in listings now include address_label and funding_tx_label (the lnd label of the funding transaction), as discussed.
• Renamed Utxo.label to address_label in ListUnspentDeposits, so both listings use the same name.
• Removed the label from StaticAddressSummaryResponse. It only ever referred to the legacy/root address.
• Change addresses created by withdrawals and loop-ins now inherit the labels of the deposits they spend. Distinct labels are joined with , in spend order, labels already inherited aren't repeated, and labels that would exceed the 500-character limit are dropped whole.
• Deposits and loop-in change addresses loaded from the DB now carry their address label.
• UpdateStaticAddressLabel returns gRPC NotFound for an unknown address.
• Fixed the shared --label help text (missing space), and gave listswaps --label its own help, since there it's a filter.