fix(wallet): route switch stop by process-handle ownership, not the external latch

Live logs showed the app usually just DIRECT-CONNECTS to an already-running
dragonxd (config found → connect; EmbeddedDaemon::start() never called). Two
consequences broke the switch: no process handle, and externalDaemonDetected()
stays false (it's only latched inside start()). So a direct-connected node was
treated as "owned" → stopEmbeddedDaemon() → an autoDetectConfig() temp RPC stop
that never reached the daemon → the node never stopped → the ~40s port poll timed
out → "the running node didn't release its connection in time" revert.

Gate on the real ownership signal — whether we hold a live process handle
(isEmbeddedDaemonRunning()) — instead of the unreliable externalDaemonDetected():
- stopDaemonForWalletSwitch: owned (we spawned it) → stopEmbeddedDaemon() with
  SIGTERM/SIGKILL; NOT owned (adopted or direct-connect, no handle) → RPC "stop"
  over the exact creds we're connected with (saved_config_), which is guaranteed
  to reach our node. Then the unchanged port-free poll.
- switchToWallet confirm gate: show "Stop the running node?" when connected to a
  node this session didn't spawn (state_.connected && !isEmbeddedDaemonRunning()).
- Fixes beginAdoptSeedWallet's direct-connect case identically (shared helper).

Adversarially verified (6/6): ownership signal, saved_config_ delivery incl.
cookie auth, foreign-daemon safety, confirm gate, seed-adopt, re-ownership/revert.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/app_network.cpp

@@ -1056,11 +1056,11 @@ void App::switchToWallet(const std::string& walletFile, bool stopDaemonConfirmed
         ui::Notifications::instance().warning("Finish or cancel the pending send before switching wallets.");
         return;
     }
-    // The node we'd restart may be one this session ADOPTED — a dragonxd already running when the wallet
-    // launched (left running by "keep node running", or started by the user). Switching must stop+restart
-    // it on the new wallet, so confirm first rather than killing a node the user may have kept up on
-    // purpose. (An owned node we started this session restarts silently, as before.)
-    if (!stopDaemonConfirmed && daemon_controller_ && daemon_controller_->externalDaemonDetected()) {
+    // If we're connected to a node this session did NOT spawn (no live process handle — it was left
+    // running by "keep node running", started by the user, or we just direct-connected to a config-provided
+    // one), confirm before stopping it: switching must stop+restart it on the new wallet, but the user may
+    // have kept it running on purpose. A node we started ourselves (handle held) restarts silently.
+    if (!stopDaemonConfirmed && state_.connected && !isEmbeddedDaemonRunning()) {
         pending_switch_wallet_file_ = walletFile;
         show_switch_stop_daemon_confirm_ = true;
         return;