fix: handle counterparty channel closes

[jvsena42]

Closes #802 (comment)

This PR:

1. Adds counterparty channel close detection and user notification via a "Connection Closed" sheet
2. Creates transfer records for counterparty-initiated channel closes (force and cooperative)
3. Improves syncTransferStates to handle batched force-close sweeps correctly

Description

• Classifies ClosureReason variants to detect counterparty-initiated closes (force close vs cooperative)
• Creates a transfer when a counterparty closes a channel, looking up the channel balance from lightning balances or closed channel records
• Shows a "Connection Closed" bottom sheet to inform the user
• Adds PendingSweepBalance extension functions for extracting channel IDs and spending txids
• Improves force close settlement logic in syncTransferStates: checks on-chain activity for the channel, falls back to pending sweep status, and handles batched sweeps where LDK links a single transaction to multiple channels
• Adds helper methods in CoreService.ActivityService for querying on-chain activity by channel or txid
• Adds unit tests for the new force close sync scenarios

Preview

coop-close.webm

counterparty-coop-close.webm

conterparty-force-close.webm

force-close-settle.webm

The timestamps didn't change because of a bug caused by fast mining 146 blocks DataException: confirm_timestamp must be greater than or equal to timestamp

QA Notes

for counterparty closing use the slack command /regtest-ln-close-channel <fundingTx:vout> [force]

1. Counterparty force close detection

   • In regtest, open a channel with the LSP
   • Force close the channel from the LSP side
   • Mine 1 block
   • Verify the "Connection Closed" sheet appears
   • Mine 146 blocks
   • Verify a transfer banner appears on the savings screen tracking the sweep

2. ** Counterparty cooperative close detection**

   • Trigger a cooperative close from the counterparty
   • Verify the transfer is created
   • Verify the spending balance is imediately subtracted

3. Cooperative close detection

   • Transfer to spending flow
   • Verify the transfer is created
   • Verify the spending balance is imediately subtracted

[pwltr]

The easier way of triggering a force-close on Blocktank side is simulating #802 bug

Can also use the staging bot /regtest-ln-close-channel <fundingTx:vout> [force]

[jvsena42]

E2E

https://github.com/synonymdev/bitkit-android/actions/runs/22494919042