LND

config: check cltv expiry policy range

Check configured and advertised forwarding CLTV deltas against max-cltv-expiry
so local configuration and advertised channel policy stay within the same
supported range.

htlcswitch+invoices: align final-hop CLTV handling

Apply the same supported CLTV delta range to final-hop HTLC handling that is
already used for forwarding.

Use a shared helper for the exit-hop link path so final-hop amount and CLTV
checks remain consistent across invoice creation and HTLC handling.

docs: add release note for DNS fallback SRV lookup panic fix 0.21.1

docs: remove release note for DNS fallback panic of 0.22.0

multi: fix lint findings from btcd v2 migration

The btcd v2 module migration re-touched several lines that the line-length
linter then flagged, and left one error return unchecked. Wrap the
over-length lines in input/test_utils.go and zpay32 (the address-decode
helpers and test fixtures whose btcutil->address rename lengthened them),
and check the LoadTxFilter error return in routing/chainview/btcd.go.

multi: upgrade to btcd v2 modules

Migrate all btcd dependencies to the new per-package v2 modules (wire/v2,
txscript/v2, chaincfg/v2, chainhash/v2, btcutil/v2, psbt/v2, btcec/v2)
introduced by btcd v0.26.0, and pin the tagged ecosystem versions:
btcwallet v0.17.0, neutrino v0.18.0 and lightning-onion v1.4.0.

The bulk of the import rewrite was produced by the scripted diff from
https://github.com/btcsuite/btcd/pull/2547 (followed by 'make rpc'). The
address symbols that moved out of btcutil into the new address package
are imported as btcaddr where a local "address" variable would otherwise
shadow them. The go.mod/go.sum updates and the remaining manual
compilation fixes are folded into this single commit so it builds on its
own (the migration was previously split into a reproducible scripted-diff
plus follow-ups, intended to be squashed on merge).

docs: add release note for DNS fallback SRV lookup panic fix

discovery: fix panic in DNS fallback SRV lookup

The fallback SRV lookup type-asserted each DNS Answer record to *dns.SRV
unconditionally. If the response contains a non-SRV record (e.g. an A or
CNAME), the type assertion panics and crashes the daemon. Use the
comma-ok form to skip non-SRV records instead.

Also guard against an empty LookupHost result for the shim, which would
otherwise panic on an out-of-bounds index into addrs.

This is safe to discuss and fix in public. The bug is very unlikely to be
exploitable: triggering it requires either a DNS seeder to serve a
malformed response, or an on-path MITM injecting one (the fallback
response is unauthenticated). A malicious seeder already has far more
direct ways to disrupt a node, and a MITM attack is hard to mount, so the
panic does not meaningfully widen the attack surface.

lnrpc: document reply_path verbatim passthrough on OnionMessageUpdate

Document that the introduction_node field in an OnionMessageUpdate's
reply_path is passed through verbatim from the wire, potentially
carrying either a 33-byte pubkey or a 9-byte sciddir form. Subscribers
wishing to reply must resolve sciddir forms against their local channel
graph.

The SubscribeOnionMessages bridge is refactored to use a new
marshallBlindedPath helper, ensuring a nil reply path remains nil in the
RPC response rather than being emitted as an empty struct.

tor: skip onion cleanup before service creation

Only send DEL_ONION if ADD_ONION completed successfully and the
controller has an active service ID to remove.

This avoids masking the original ADD_ONION failure with a secondary
empty DEL_ONION error during startup cleanup.

rpcperms: recover RPC handler panics

github: add gateway code-review workflow (#10910)

* github: add gateway code-review workflow

Opt-in review bot invoked via /gateway review PR comments (maintainer-gated).
Thin shim onto the public lightninglabs/gateway-action (SHA-pinned to v0.4.3);
the review runtime stays private. Comment-commands only, so fork PRs never
spawn failing runs.

* github: address review on gateway workflow

- Gate the job on a /gateway command in the comment body so unrelated PR
comments don't spin up no-op runners. Use contains() (not startsWith) since
the runtime accepts the command at column 0 of any line, incl. multi-line.
- Pin runtime_ref to the gateway commit SHA so runtime upgrades require an lnd
PR rather than a moved tag, matching the action SHA-pin.

docs: add 0.21.1 release notes

build: update tor module to v1.1.7

dev.Dockerfile: use cache mounts to speed up rebuilding

docs: add release notes for offline peer uptime fix

chanfitness: seed peer uptime from actual online state

Channels are loaded into the channel fitness store on startup regardless
of whether their peer is connected. When a peer monitor was first
created we unconditionally recorded an online event, which caused
offline peers to report 100% uptime in ListChannels.

Seed the initial event with the peer's actual connection state via a new
IsPeerOnline config callback so that uptime reflects real connectivity.

tor: use latest btcd

tlv: use btcd v2 submodules

routerrpc: document default timeout for EstimateRouteFee probes

The RouteFeeRequest.timeout field did not document its behavior when
unset or explicitly set to zero. This is easy to misread as "no
timeout", i.e. an unbounded, uncancellable probe, especially given the
adjacent note that canceling the context does not stop the payment
loop.

In practice the probe path runs through SendPaymentV2, which replaces a
zero timeout_seconds with DefaultPaymentTimeout (60 seconds) before
dispatching the probe. A zero or unset timeout therefore falls back to
the same 60 second default that SendPaymentRequest.timeout_seconds
already documents.

Mirror that wording on RouteFeeRequest.timeout so the zero-value
behavior is explicit, and update the generated gRPC stub and swagger
description to match. Documentation only; no behavior change.

ci: require OTS proofs for final releases

kvdb: bump pgx to v5.9.2

sqldb/v2: bump pgx to v5.9.2

sqldb: bump pgx to v5.9.2

lnd: bump pgx to v5.9.2