fix(lnd): make the seed-backup notification actually open the backup flow

Clicking 'Back up now' on the Lightning seed banner only navigated to
the LND app page — and the backup card there hid itself permanently if
its single status fetch failed (common right after a fresh install),
so the click appeared to do nothing.

The banner now deep-links with ?seed-backup=1, which the LND page uses
to open the reveal flow directly, and the card retries its status fetch
with backoff instead of giving up after one failed RPC.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

neode-ui/src/components/LndSeedBackupPrompt.vue

@@ -101,7 +101,10 @@ const show = computed(() =>
 )
 
 function backUpNow() {
-  router.push(LND_DETAILS_PATH).catch(() => {})
+  // seed-backup=1 makes the LND page open the reveal flow immediately —
+  // landing on the app page with the card below the fold read as
+  // "clicking the notification did nothing".
+  router.push({ path: LND_DETAILS_PATH, query: { 'seed-backup': '1' } }).catch(() => {})
 }
 
 function snooze() {