test: update lnd to v0.21.2-beta

[openoms]

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[openoms]

Monitoring update from the reruns on 6f29ca1b:

• Core integration: both attempts reached Buck's outer 10-minute rule timeout. A local reproduction completed all 46 suites / 254 tests successfully (342.382 s in Jest), so this was a harness timeout rather than a functional failure. The new 48f7e721 commit adds the appropriate target-specific 20-minute timeout; fresh CI is now exercising it.
• E2E: the rerun was cancelled at the workflow's 40-minute limit after reaching test 132/244, but increasing that timeout alone would not fix it. The uploaded Tilt log shows lightning@10.26.1 failing on an LND 0.21 channel event with ExpectedEventTypeInChannelSubscription. The client then cancels the channel subscription. A later locally initiated channel open is missed, its 3,850-sat fee is not booked, galoy_lndBalanceSync stays off by 3,850 sats, and the remaining accounting failures cascade from there.

The dependency versions currently pinned here (lightning@10.26.1, ln-service@57.26.1) only declare support through LND 0.19.2. The first releases declaring LND 0.21.1 support are lightning@12.1.2 and ln-service@59.1.2; both require Node >=22.

Recommended path:

1. Land or explicitly stack this PR on chore(node): bump Node.js from 20 to v24.19.0 (LTS "Krypton") #770 (Node 24).
2. Upgrade lightning and ln-service to LND 0.21.1-compatible versions and regenerate the lockfile.
3. Rerun Core and E2E. Keep the scoped Core timeout change, but do not extend the E2E timeout until the subscription incompatibility is fixed.

Relevant runs: Core integration, E2E.