daemon version check, idle mining control, bootstrap mirror, import key paste, and cleanup

- Add startup binary version checking for dragonxd/xmrig
- Display daemon version in UI
- Add idle mining thread count adjustment
- Add bootstrap mirror option (bootstrap2.dragonx.is) in setup wizard
- Add paste button to import private key dialog with address validation
- Add z-address generation UI feedback (loading indicator)
- Add option to delete blockchain data while preserving wallet.dat
- Add font scale slider hotkey tooltip (Ctrl+Plus/Ctrl+Minus)
- Fix Windows RPC auth: trim \r from config values, add .cookie fallback
- Fix connection status message during block index loading
- Improve application shutdown to prevent lingering background process

build.sh

@@ -617,6 +617,10 @@ HDR
         [[ -f "$DD/$f" ]] && cp "$DD/$f" "$dist_dir/"
     done
 
+    # Bundle xmrig for mining support
+    local XMRIG_WIN="$SCRIPT_DIR/prebuilt-binaries/xmrig-hac/xmrig.exe"
+    [[ -f "$XMRIG_WIN" ]] && { cp "$XMRIG_WIN" "$dist_dir/"; info "Bundled xmrig.exe"; } || warn "xmrig.exe not found — mining unavailable in zip"
+
     cp -r bin/res "$dist_dir/" 2>/dev/null || true
 
     # ── Single-file exe (all resources embedded) ────────────────────────────