fix(lite): render a lite send as a negative debit, not a green "+"; recover unauthored-send amounts

Lite-parity audit, two History-correctness findings (display/parse only — no send/broadcast call touched):
- A lite send carried a POSITIVE tx.amount, so History, the Details dialog and CSV export rendered an
  outgoing payment as a green "+" receipt (the full node uses a negative debit). The mapper already
  computes signedAmountZatoshis (negative for sends, positive for receives); applyLiteRefreshModelToWalletState
  now uses it for tx.amount, so the shared UI shows a red "-" and CSV a negative value. The summary cards
  use std::abs and are unaffected.
- A send this wallet did not author (seed restore / another device) has empty outgoing_metadata, so the
  parser summed it to 0 and showed amount 0 with a blank address, understating Sent totals. parseTransactionRecord
  now falls back to |record.amount| (the net debit, incl. fee) when the metadata sum is 0, tolerant of a
  missing/odd field; explicit outgoing_metadata still wins.

Tests: testLiteSendAmountIsNegative (send maps to <0, receive stays >0) and
testLiteForeignSendFallsBackToRecordAmount.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/wallet/lite_result_parsers.cpp

@@ -349,6 +349,15 @@ bool parseTransactionRecord(const json& value,
             output.amount += parsedOutput.value;
             output.outgoingMetadata.push_back(std::move(parsedOutput));
         }
+        // A send this wallet did not author (seed restore / other device) has empty outgoing_metadata,
+        // so the sum is 0. Fall back to the record's net 'amount' magnitude (includes the fee) so Sent
+        // totals aren't understated. Display-only; tolerant of a missing/odd field.
+        if (output.amount == 0 && value.contains("amount") && !value.at("amount").is_null()) {
+            std::int64_t net = 0;
+            if (jsonToSigned(value.at("amount"), net) && net != std::numeric_limits<std::int64_t>::min()) {
+                output.amount = net < 0 ? -net : net;
+            }
+        }
         return true;
     }