Local dashboard: plain-language status checklist and C2-free listening

- /api/health: ordered checklist (password, C2 approval, MQTT, SDR, source,
  OP25, decoding, audio, Icecast) with what's wrong and what to do; pure
  build_checks() so every state (incl. Toughny's unapproved node) is tested
- /api/listen: pick P25 control channels / one analog freq / a cached C2
  system, validated in MHz, stored as a local override; OP25 restarted with
  the start failure reason surfaced
- /api/config/system no longer writes a raw blob OP25 can't read
- OP25 resumes after reboot on a locally chosen system, not only C2-assigned
- op25-container: analog (NBFM) config generation fixed (AttributeError +
  wrong field names), /op25/log tail, start refuses without a config,
  status detects a dead multi_rx ("crashed") -- node-26#12
- index.html rebuilt on UI_REDESIGN tokens; scanner drops DMR, shows System key

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

drb-edge-node/app/templates/scanner.html

@@ -171,15 +171,14 @@
       <h3 style="color: var(--dept-color); margin-bottom: 6px; font-size: 13px;">Or Enter Freq Manually:</h3>
       <div style="display: grid; grid-template-columns: 1fr 1fr; gap: 5px; font-size: 11px; margin-bottom: 8px;">
         <div>
-          <label>Control Freq (MHz/Hz):</label>
+          <label>Freq (MHz) — P25 control channel or analog:</label>
           <input type="text" id="manual-freq" style="background:#222; color:#fff; border:1px solid #555; padding:3px; width:100%; border-radius:2px;">
         </div>
         <div>
           <label>System Type:</label>
           <select id="manual-type" style="background:#222; color:#fff; border:1px solid #555; padding:3px; width:100%; border-radius:2px;">
             <option value="P25">P25</option>
-            <option value="DMR">DMR</option>
-            <option value="NBFM">NBFM</option>
+            <option value="NBFM">Analog FM</option>
           </select>
         </div>
       </div>
@@ -208,7 +207,7 @@
 
   <div class="softkeys">
     <div class="softkey">VOL (+/-)</div>
-    <div class="softkey">HOLD (H)</div>
+    <div class="softkey">SYSTEM (S)</div>
     <div class="softkey">PLAY (P)</div>
   </div>
 
@@ -309,7 +308,7 @@
       const container = document.getElementById('system-list');
       container.innerHTML = '';
       if (systems.length === 0) {
-        container.innerHTML = '<div style="padding: 10px; color: #888;">No cached systems found.</div>';
+        container.innerHTML = '<div style="padding: 10px; color: #888;">No server systems saved yet (they arrive once the node is approved). Enter a frequency below.</div>';
         return;
       }
       systems.forEach((sys, index) => {