feat(diagnostics): add "Copy diagnostics" + "Open log folder" actions (Foundation QoL)

Settings (logging section) gains two support-friendly actions, now that the logging
foundation actually produces logs (W7-2):

- Open log folder: opens the config dir (Platform::openFolder) so users can find
  dragonx-debug.log / dragonx-crash.log.

- Copy diagnostics: copies a plaintext support snapshot to the clipboard via the new
  App::buildDiagnosticsReport() — version, build variant, platform, connection status,
  active wallet path + existence + size, encryption/lock state, sync heights, and (full-
  node) daemon status/running/crash-count/lastError, plus the log paths. No secrets.

Build-clean; ctest 1/1. Remaining QoL: persistent alert history, a daemon/RPC error
banner, and the W6-2 refresh-staleness badge. See docs/wallet-hardening.md.

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

docs/wallet-hardening.md

@@ -21,7 +21,7 @@ Status legend: ☐ not started · ◐ in progress · ☑ landed & verified
 | **P1-A** | W3-1, W3-2, W3-4 ✓ · W3-3 ⚑ | Migrate-to-seed correctness (fund-adjacent) | ◐ 3/4 |
 | **P1-B** | W1-1, W1-2, W1-3, W1-4 ✓ + startup guard | Missing/wrong wallet-file safety | ☑ |
 | **P2**  | W5-1, W5-2, W6-1, W6-3 ✓ · W6-2 ☐ | Stale state & lite save-failure surfacing | ◐ 4/5 |
-| **F**   | W7-2, W7-3, W7-4 ✓ · QoL ☐ | Diagnostics foundation + QoL bundle | ◐ infra done |
+| **F**   | W7-2, W7-3, W7-4 ✓ · QoL: copy-diag + open-log ✓, alert-history/error-banner/staleness ☐ | Diagnostics foundation + QoL bundle | ◐ |
 
 ---
 
@@ -112,6 +112,7 @@ Land W7-2 first — it unblocks the rest.
 
 ## Progress log
 
+- **Foundation QoL / "Copy diagnostics" + "Open log folder"** — ☑ landed: Settings (logging section) now has two actions. **Open log folder** opens the config dir (`Platform::openFolder`) so users can actually find `dragonx-debug.log`/`dragonx-crash.log`. **Copy diagnostics** copies a plaintext support snapshot to the clipboard via the new `App::buildDiagnosticsReport()` — version, build variant, platform, connection status, active wallet path + existence + size, encryption/lock state, sync heights, daemon status/running/crash-count/lastError (full-node), and the log paths. No secrets. Build-clean; `ctest` 1/1. **Remaining QoL:** persistent alert history, a daemon/RPC error banner, and the W6-2 refresh-staleness badge.
 - **Foundation / W7-2 · W7-3 · W7-4 (diagnostics infrastructure)** — ☑ landed (answers the original "easier to diagnose" ask — the logging/crash foundation now actually works):
   - **W7-2 (Med, keystone):** the app-level `Logger` file sink was never initialized, so `LOG`/`LOGF`/`VERBOSE_LOGF` went nowhere and `dragonx-debug.log` didn't exist on Linux/macOS at all. `main()` now calls `Logger::init(<config>/dragonx-debug.log)` on all platforms. Also fixed a **latent deadlock** this exposed: `init()` wrote its banner via `write()`, which re-locks the non-recursive `mutex_` it already holds — now written directly. On Windows the raw stdout/stderr `freopen` was moved to a separate `dragonx-stdout.log` so the two writers don't contend. New `testLoggerFileSink` (also a deadlock guard — it would hang if that regressed).
   - **W7-3 (Med):** no crash handler existed on Linux/macOS. Added an **async-signal-safe** `sigaction` handler (SIGSEGV/ABRT/BUS/FPE/ILL) that writes a signal id + `backtrace_symbols_fd` backtrace to `dragonx-crash.log`, then re-raises the default disposition for a core dump — the POSIX counterpart of the Windows SEH filter.

src/app.cpp

@@ -105,6 +105,7 @@
 #include <unordered_set>
 #include <fstream>
 #include <filesystem>
+#include <sstream>
 #include <thread>
 #include <chrono>
 #include <exception>
@@ -5658,6 +5659,62 @@ void App::maybeFinishTransactionSendProgress()
     if (addresses_dirty_ || network_refresh_.jobInProgress(Job::Addresses)) return;
     send_progress_active_ = false;
 }
+std::string App::buildDiagnosticsReport()
+{
+    std::ostringstream os;
+    os << "=== ObsidianDragon diagnostics ===\n";
+    os << "version: " << DRAGONX_VERSION << "\n";
+#if DRAGONX_LITE_BUILD
+    os << "variant: Lite\n";
+#else
+    os << "variant: Full-node\n";
+#endif
+#if defined(_WIN32)
+    os << "platform: windows\n";
+#elif defined(__APPLE__)
+    os << "platform: macos\n";
+#else
+    os << "platform: linux\n";
+#endif
+    os << "connected: " << (state_.connected ? "yes" : "no") << "\n";
+    os << "status: " << connection_status_ << "\n";
+
+    const std::string activeWallet = settings_ ? settings_->getActiveWalletFile() : std::string("(none)");
+    os << "active wallet: " << activeWallet << "\n";
+    {
+        std::error_code ec;
+        const std::string wp = util::Platform::getDragonXDataDir() + "/" + activeWallet;
+        const bool present = std::filesystem::exists(wp, ec);
+        os << "  path: " << wp << (present ? "  [present" : "  [MISSING");
+        if (present) { auto sz = std::filesystem::file_size(wp, ec); if (!ec) os << ", " << sz << " bytes"; }
+        os << "]\n";
+    }
+    os << "encryption: "
+       << (state_.encryption_state_known
+               ? (state_.encrypted ? (state_.locked ? "encrypted, locked" : "encrypted, unlocked") : "unencrypted")
+               : "unknown")
+       << "\n";
+    os << "sync: block " << state_.sync.blocks << " / " << state_.sync.headers
+       << (state_.sync.syncing ? "  (syncing)" : "")
+       << (state_.warming_up ? "  (warming up)" : "") << "\n";
+
+#if !DRAGONX_LITE_BUILD
+    os << "daemon status: " << daemon_status_ << "\n";
+    if (daemon_controller_) {
+        os << "daemon running: " << (daemon_controller_->isRunning() ? "yes" : "no")
+           << ", crashes: " << daemon_controller_->crashCount() << "\n";
+        const std::string derr = daemon_controller_->lastError();
+        if (!derr.empty()) os << "daemon lastError: " << derr << "\n";
+    }
+#endif
+
+    const std::string cfg = util::Platform::getObsidianDragonDir();
+    os << "log folder: " << cfg << "\n";
+    os << "  " << cfg << "/dragonx-debug.log\n";
+    os << "  " << cfg << "/dragonx-crash.log\n";
+    return os.str();
+}
+
 void App::restartDaemon()
 {
     if (!supportsFullNodeLifecycleActions()) {

src/app.h

@@ -147,6 +147,10 @@ public:
     bool isLiteBuild() const { return wallet::isLiteBuild(walletCapabilities()); }
     bool supportsEmbeddedDaemon() const { return wallet::supportsEmbeddedDaemon(walletCapabilities()); }
     bool supportsFullNodeLifecycleActions() const { return wallet::supportsFullNodeLifecycleActions(walletCapabilities()); }
+
+    // W7 QoL: a plaintext support-diagnostics snapshot (version, variant, daemon/RPC/wallet/log state)
+    // for the "Copy diagnostics" action. Contains no secrets.
+    std::string buildDiagnosticsReport();
     bool supportsSoloMining() const { return wallet::supportsSoloMining(walletCapabilities()); }
     bool supportsPoolMining() const { return wallet::supportsPoolMining(walletCapabilities()); }
     bool supportsLiteBackend() const { return wallet::supportsLiteBackend(walletCapabilities()); }

src/ui/pages/settings_page.cpp

@@ -1351,6 +1351,21 @@ void RenderSettingsPage(App* app) {
             if (ImGui::IsItemHovered()) material::Tooltip("%s", TR("tt_verbose"));
         }
 
+        // W7 QoL: quick diagnostics actions — open the log folder, and copy a plaintext support bundle
+        // (version, variant, daemon/RPC/wallet/log state) to the clipboard.
+        {
+            const float diagBtnW = (contentW - Layout::spacingMd()) * 0.5f;
+            if (TactileButton(TR("settings_open_log_folder"), ImVec2(diagBtnW, 0), S.resolveFont("button")))
+                dragonx::util::Platform::openFolder(dragonx::util::Platform::getObsidianDragonDir());
+            if (ImGui::IsItemHovered()) material::Tooltip("%s", TR("tt_open_log_folder"));
+            ImGui::SameLine(0, Layout::spacingMd());
+            if (TactileButton(TR("settings_copy_diagnostics"), ImVec2(diagBtnW, 0), S.resolveFont("button"))) {
+                ImGui::SetClipboardText(app->buildDiagnosticsReport().c_str());
+                ui::Notifications::instance().info(TR("settings_diagnostics_copied"), 4.0f);
+            }
+            if (ImGui::IsItemHovered()) material::Tooltip("%s", TR("tt_copy_diagnostics"));
+        }
+
         ImGui::Dummy(ImVec2(0, Layout::spacingSm()));
 
         // --- Collapsible: Tools & Actions... ---

src/util/i18n.cpp

@@ -1322,6 +1322,11 @@ void I18n::loadBuiltinEnglish()
         strings_["loading_stall_body"] = "The daemon has been initializing for %.0fs. This can be normal after an update or on first launch (loading the block index or rescanning) — it will connect automatically once ready.";
         strings_["loading_stall_hint"] = "Still stuck? Open Settings and use Restart Daemon, or check the Console for details.";
         strings_["sb_plaintext_remote_blocked"] = "Refusing to send RPC credentials over plaintext to a remote host. Add rpcallowplaintext=1 to DRAGONX.conf to allow it, or enable TLS with rpctls=1.";
+        strings_["settings_open_log_folder"] = "Open log folder";
+        strings_["settings_copy_diagnostics"] = "Copy diagnostics";
+        strings_["settings_diagnostics_copied"] = "Diagnostics copied to clipboard";
+        strings_["tt_open_log_folder"] = "Open the folder containing the debug and crash logs";
+        strings_["tt_copy_diagnostics"] = "Copy a support snapshot (version, daemon/wallet/log state — no secrets) to the clipboard";
         strings_["sb_dragonxd_running"] = "dragonxd running";
         strings_["sb_dragonxd_stopping"] = "Stopping dragonxd...";
         strings_["sb_dragonxd_stopped"] = "dragonxd stopped";