fix(lnd): give the rotation's verify step its own deadline

The mint wait and the post-rotation verify shared one 15-minute budget. A
rotation that legitimately spent 14 of those minutes waiting for LND to mint a
fresh macaroon — normal on a loaded node, where opening channel.db/graph.db/
wallet.db alone has been measured at 2m38s — then had 60 seconds to confirm the
node identity and channel census came back, and would report FAILURE on a wallet
that was completely healthy.

That is the most alarming possible way to be wrong about someone's Lightning
node: it names a backup directory and tells them to investigate before retrying,
at the exact moment nothing is actually broken. Each wait now gets its own
budget. Waiting longer costs nothing here — the failure this step exists to catch
(changed identity, missing channels) is not time-sensitive.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

core/archipelago/src/api/rpc/lnd/macaroons.rs

@@ -616,10 +616,11 @@ async fn run_rotation(
         .await
         .with_context(|| format!("unlocking the wallet — old material is in {backup}"))?;
 
-    let deadline = std::time::Instant::now() + std::time::Duration::from_secs(MACAROON_WAIT_SECS);
+    let mint_deadline =
+        std::time::Instant::now() + std::time::Duration::from_secs(MACAROON_WAIT_SECS);
     let admin_path = format!("{LND_MAINNET_DIR}/admin.macaroon");
     let mut new_digest = None;
-    while std::time::Instant::now() < deadline {
+    while std::time::Instant::now() < mint_deadline {
         if let Some(d) = digest_as_root(&admin_path).await {
             new_digest = Some(d);
             break;
@@ -644,8 +645,17 @@ async fn run_rotation(
     });
 
     // 6. Verify the things that must NOT have changed.
+    //
+    // Its own budget, deliberately not the mint deadline. Sharing one would mean
+    // a rotation that legitimately spent 14 of its 15 minutes waiting for LND to
+    // mint gets 1 minute to prove the channels came back, and then reports
+    // FAILURE on a node that is perfectly healthy — the most alarming possible
+    // way to be wrong about someone's Lightning wallet.
     with_progress(|p| p.set("verify", StepState::Running, None));
-    let (pubkey_after, census_after) = wait_for_serving(deadline).await.with_context(|| {
+    let verify_deadline =
+        std::time::Instant::now() + std::time::Duration::from_secs(MACAROON_WAIT_SECS);
+    let (pubkey_after, census_after) =
+        wait_for_serving(verify_deadline).await.with_context(|| {
             format!("verifying the node after rotation — old material is in {backup}")
         })?;
     with_progress(|p| p.channels_after = Some(census_after.channels_open));