feat(desktop): wire NamecoinSettingsSection into Settings screen

The desktop client already ships DesktopNamecoinPreferences, the
DesktopNamecoinNameService that consumes them, and the NamecoinSettingsSection
composable that's a port of the Android UI. The section just wasn't surfaced
in the desktop Settings screen.

This wires NamecoinSettingsSection into RelaySettingsScreen, between the Tor
section and the Developer / Relay sections. Preferences come from the
namecoinPreferences parameter that the deck container already passes in, and
fall back to LocalNamecoinPreferences when called from another caller.

User-visible behaviour: the .bit / d/ / id/ ElectrumX server settings (master
toggle, custom servers, defaults indicator, add/remove, reset) are now
reachable from desktop Settings and persist via java.util.prefs.Preferences.

desktopApp/src/jvmMain/kotlin/com/vitorpamplona/amethyst/desktop/Main.kt

@@ -118,6 +118,7 @@ import com.vitorpamplona.amethyst.desktop.ui.profile.ProfileInfoCard
 import com.vitorpamplona.amethyst.desktop.ui.relay.LocalRelayCategories
 import com.vitorpamplona.amethyst.desktop.ui.relay.RelayStatusCard
 import com.vitorpamplona.amethyst.desktop.ui.settings.MediaServerSettings
+import com.vitorpamplona.amethyst.desktop.ui.settings.NamecoinSettingsSection
 import com.vitorpamplona.quartz.nip01Core.relay.client.reqs.SubscriptionListener
 import com.vitorpamplona.quartz.nip01Core.relay.filters.Filter
 import com.vitorpamplona.quartz.nip01Core.relay.normalizer.NormalizedRelayUrl
@@ -1624,6 +1625,31 @@ fun RelaySettingsScreen(
             HorizontalDivider()
             Spacer(Modifier.height(24.dp))
 
+            // Namecoin Settings (ElectrumX servers for .bit / d/ / id/ resolution)
+            val namecoinPrefsHere = namecoinPreferences ?: LocalNamecoinPreferences.current
+            if (namecoinPrefsHere != null) {
+                val namecoinScope = rememberCoroutineScope()
+                val namecoinSettings by namecoinPrefsHere.settings.collectAsState()
+                NamecoinSettingsSection(
+                    settings = namecoinSettings,
+                    onToggleEnabled = { enabled ->
+                        namecoinScope.launch { namecoinPrefsHere.setEnabled(enabled) }
+                    },
+                    onAddServer = { server ->
+                        namecoinScope.launch { namecoinPrefsHere.addServer(server) }
+                    },
+                    onRemoveServer = { server ->
+                        namecoinScope.launch { namecoinPrefsHere.removeServer(server) }
+                    },
+                    onReset = {
+                        namecoinScope.launch { namecoinPrefsHere.reset() }
+                    },
+                )
+                Spacer(Modifier.height(24.dp))
+                HorizontalDivider()
+                Spacer(Modifier.height(24.dp))
+            }
+
             // Developer Settings Section (only in debug mode)
             if (DebugConfig.isDebugMode) {
                 com.vitorpamplona.amethyst.desktop.ui