fix(daemon): never restart, delete or swap under a node that hasn't exited

Every operation that stops the node (restart, rescan, repair, delete
chain data, reinstall, bootstrap, wallet switch/adopt/restore/rebuild,
wizard restart, encrypt, decrypt) now:

- refuses up front while the node is rebuilding witnesses or has not
  answered for 30s, with a "try again when it's done" warning, and sends
  no stop;
- goes ahead only once the node's PROCESS has exited, not its RPC port.
  A stop that doesn't finish within 120s cancels the operation (warning;
  a cancelled rescan/repair disarms its flags); nothing is started over
  the old node, chain data isn't deleted, wallet.dat isn't swapped.

Specifics:
- stopDaemonForWalletSwitch() no longer reports "stopped" when the app
  is quitting (adopt could swap wallet.dat under a live node).
- Decrypt waited a fixed 3s after "stop" before renaming wallet.dat; it
  now waits for the process to exit, and scrubs the key export if not.
- Bootstrap waits for the process before cleanChainData and stops the
  node through the stop routine instead of the shared RPC client.
- StopScope::Connected lets switch/reinstall/decrypt stop an adopted or
  external node through the same never-kill routine.
- A bounded stop that can't reach the node (a foreign node refusing our
  credentials) gives up after 5s instead of 120s.
- macOS: isDaemonProcessRunning() checks processes (libproc), not the
  RPC port.
- rpcBusyWhileAlive() also reads the busy gate: since the gate, the
  first timeout usually lands on another lane and the 30s clock never
  started (also weakened the quit prompt for a silent rebuild).
- Notifications render during the first-run wizard.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/util/bootstrap.cpp

@@ -162,11 +162,17 @@ void Bootstrap::start(const std::string& dataDir, const std::string& url) {
             worker_running_ = false;
             return;
         }
-        // Step 3: Ensure daemon is fully stopped before touching chain data
+        // Step 3: Ensure daemon is fully stopped before touching chain data. Gone means the PROCESS has
+        // exited, not just its RPC port: dragonxd unbinds RPC early in its shutdown and keeps its files
+        // (and the datadir lock) until it exits — deleting chain data under it corrupts it, or fails on
+        // Windows' locked files.
         {
             setProgress(State::Extracting, "Waiting for daemon to stop...");
+            auto daemonUp = [] {
+                return daemon::EmbeddedDaemon::isRpcPortInUse() || daemon::EmbeddedDaemon::isDaemonProcessRunning();
+            };
             int waited = 0;
-            while (daemon::EmbeddedDaemon::isRpcPortInUse() && waited < 60 && !cancel_requested_) {
+            while (daemonUp() && waited < 120 && !cancel_requested_) {
                 std::this_thread::sleep_for(std::chrono::seconds(1));
                 waited++;
                 if (waited % 5 == 0)
@@ -177,7 +183,7 @@ void Bootstrap::start(const std::string& dataDir, const std::string& url) {
                 worker_running_ = false;
                 return;
             }
-            if (daemon::EmbeddedDaemon::isRpcPortInUse()) {
+            if (daemonUp()) {
                 setProgress(State::Failed, "Daemon is still running — stop it before using bootstrap");
                 worker_running_ = false;
                 return;