feat(panel): edit memoryMB from the Settings modal

Adds GET/POST /api/daemon/config (safe subset of server-config.json --
just memoryMB for now) and a "Resources" section in the existing Settings
modal. The Save and Save+restart buttons now POST both /api/server/settings
and /api/daemon/config; restartRequired is OR'd across the two endpoints.

Future fields like backupKeep / backupSchedule / bluemapDir can be added
by extending DAEMON_FIELDS in settings.js + the validation block in
RunCommand.cs. Sensitive fields (passwords, manifestUrl, ports) are
intentionally kept off this endpoint.

server/wwwroot/index.html

@@ -263,8 +263,15 @@
             <button class="modal-close" aria-label="Close">×</button>
         </div>
         <p style="font-size: 12px; color: var(--text-muted); margin: 0 0 14px;">
-            These map to <code>server.properties</code>. MC reads them at startup, so changes need a server restart to take effect.
+            These map to <code>server.properties</code> and the daemon config. MC reads them at startup, so changes need a server restart to take effect.
         </p>
+
+        <div class="settings-section-label">Resources</div>
+        <div class="settings-grid">
+            <label>Memory (MB)<input id="ssfMemoryMB" type="number" min="1024" max="65536" step="256" /></label>
+        </div>
+
+        <div class="settings-section-label" style="margin-top: 14px;">MC server.properties</div>
         <div class="settings-grid">
             <label>MOTD<input id="ssfMotd" type="text" /></label>
             <label>Gamemode<select id="ssfGamemode">