fix(settings): scope portfolio groups by wallet identity

Market-tab portfolio groups were tied to a wallet by a hash of its
address set. That hash changed whenever an address was added, so a
group built for a wallet could silently drop out of view once the
wallet gained a new address.

- Groups are now scoped by the wallet's stable id, which is persisted
  and never derived from the address set, so adding an address can no
  longer orphan a group.
- An older build's address-hash scope fails open (the group stays
  visible) and is migrated once per wallet per session to the stable id.
  A legacy group is claimed when its old hash matches, when one of its
  own addresses belongs to this wallet, or when only one wallet is
  known; anything ambiguous is left legacy and stays visible.
- Scope filtering waits until the wallet's addresses are loaded, so a
  group never flashes an empty 0.0000 balance and Add stays disabled
  until the wallet is resolved. This works on Lite, which never stamps
  an address-update time.

Behaviour: an older build opened after this change hides groups tagged
with a stable "w:" scope (they are not deleted and return on the next
upgrade) - worth a release note.

Tests: group visibility across global, stable and legacy scopes with the
wallet resolved and not; the migration rules (hash match, address
overlap, single-wallet claim, ambiguous left alone, idempotent); and a
save/load round trip where an address-set change cannot orphan the scope.

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

src/app_network.cpp

@@ -1520,6 +1520,27 @@ std::string App::activeWalletScopeId()
     return id;
 }
 
+std::string App::portfolioScopeId()
+{
+    if (capture_mode_) return "w:sweep-demo";   // in-memory only: Settings/WalletIndex saves are latched in a sweep
+    if (state_.z_addresses.empty() && state_.t_addresses.empty()) return std::string();   // not loaded yet
+    return activeWalletScopeId();
+}
+
+void App::reattachLegacyPortfolioScopes()
+{
+    if (!settings_ || capture_mode_ || !state_.connected) return;
+    const std::string scopeId = portfolioScopeId();
+    if (scopeId.empty() || scopeId == portfolio_scope_migrated_for_) return;
+    portfolio_scope_migrated_for_ = scopeId;   // once per wallet per session (re-runs after a wallet switch)
+    std::set<std::string> mine;
+    for (const auto& a : state_.z_addresses) if (!a.address.empty()) mine.insert(a.address);
+    for (const auto& a : state_.t_addresses) if (!a.address.empty()) mine.insert(a.address);
+    const int moved = settings_->reattachLegacyPortfolioScopes(
+        scopeId, activeWalletIdentityHash(), mine, wallet_index_.entries().size() <= 1);
+    if (moved > 0) settings_->save();          // UI thread, once
+}
+
 void App::updateWalletIndexForActiveWallet(bool markOpened)
 {
     if (!settings_) return;