chore(frontend): Remove Engagement Policy section and fix engage button

- Remove Engagement Policy card (targeting, assess window, cursor mode)
- Remove developer hints (externalDetect, externalFeatures, externalTrack)
- Remove manual targeting hint in Tab 2
- Fix renderLiveRadar undefined error
- Re-enable engage button after reason completes

frontend/index.html

@@ -106,41 +106,8 @@
             </label>
           </div>
 
-          <div class="hint mt-sm" id="detectorHint">
-            If the browser model cannot load (offline), plug in your own detector in <span
-              class="kbd">externalDetect()</span>.
-          </div>
         </div>
 
-        <div class="card">
-          <h2>Engagement Policy</h2>
-          <div class="grid2">
-            <div>
-              <label>Targeting</label>
-              <select id="policyMode">
-                <option value="auto">Auto: highest lethality margin</option>
-                <option value="manual">Manual: click target</option>
-              </select>
-            </div>
-            <div>
-              <label>Assess window (s)</label>
-              <input id="assessWindow" type="range" min="0.3" max="3.0" step="0.1" value="1.0" />
-              <div class="row"><small class="mini"><span id="assessWindowVal">1.0</span> s</small><small
-                  class="mini">post-dwell</small></div>
-            </div>
-          </div>
-
-          <div class="row">
-            <label>Show agent cursor</label>
-            <select id="cursorMode">
-              <option value="on">On</option>
-              <option value="off">Off</option>
-            </select>
-          </div>
-
-          <div class="hint">The UI is wired for your APIs. Replace <span class="kbd">externalDetect()</span>, <span
-              class="kbd">externalFeatures()</span>, and <span class="kbd">externalTrack()</span> when ready.</div>
-        </div>
 
         <div class="card" style="flex:1; min-height:0">
           <h2>System Log</h2>

frontend/js/main.js

@@ -452,7 +452,6 @@ document.addEventListener("DOMContentLoaded", () => {
 
                 // Trigger resize/render for Tab 2
                 resizeOverlays();
-                renderLiveRadar();
             }
 
             // Start polling for completion
@@ -467,6 +466,9 @@ document.addEventListener("DOMContentLoaded", () => {
 
                 // Seed tracks for Tab 2
                 seedTracksFromTab1();
+
+                // Re-enable engage button
+                if (btnEngage) btnEngage.disabled = false;
             }).catch(err => {
                 log(`Polling error: ${err.message}`, "e");
                 stopStreamingMode();
@@ -490,6 +492,8 @@ document.addEventListener("DOMContentLoaded", () => {
                 btnReason.style.cursor = "pointer";
             }
             if (btnCancelReason) btnCancelReason.style.display = "none";
+            // Re-enable engage button in case of failure
+            if (btnEngage) btnEngage.disabled = false;
         }
     }