Add active slice first-screen receipt

public/app.js

@@ -196,6 +196,33 @@ function renderHandoffStatus(handoff = {}) {
   `;
 }
 
+function renderFirstScreen(firstScreen = {}) {
+  if (!firstScreen.headline) return '';
+  const held = firstScreen.holdBack || [];
+  const guardrails = firstScreen.guardrails || [];
+  return `
+    <section class="active-slice-strip" aria-label="Active build slice">
+      <div class="active-slice-main">
+        <span>One thing to do now</span>
+        <h3>${escapeHtml(firstScreen.headline)}</h3>
+        <p>${escapeHtml(firstScreen.primaryAction || 'Run the smallest manual proof before product machinery.')}</p>
+      </div>
+      <div>
+        <span>Proof question</span>
+        <p>${escapeHtml(firstScreen.proofQuestion || 'What evidence would change this order?')}</p>
+      </div>
+      <div>
+        <span>Why this wins</span>
+        <p>${escapeHtml(firstScreen.why || 'It is the best first proof slice.')}</p>
+      </div>
+      ${held.length ? `<div><span>Hold back</span><ul>${held.map((item) => `<li><b>${escapeHtml(item.title)}</b>${item.lane ? ` — ${escapeHtml(item.lane)}` : ''}</li>`).join('')}</ul></div>` : ''}
+      ${guardrails.length ? `<small>Guardrails: ${guardrails.map(escapeHtml).join(' · ')}</small>` : ''}
+      ${firstScreen.sourceAnchor ? `<small>Source anchor: ${escapeHtml(firstScreen.sourceAnchor)}</small>` : ''}
+      <small>${escapeHtml(firstScreen.rule || 'One active move. Everything else waits.')}</small>
+    </section>
+  `;
+}
+
 function renderDecisionReceipt(receipt = {}) {
   if (!receipt.activeMove) return '';
   const held = receipt.doNotStartYet || [];
@@ -348,6 +375,7 @@ function renderResults(data) {
       <div><span>Proof to collect</span><p>${escapeHtml(glance.evidenceQuestion || 'Name the evidence that would change the ranking.')}</p></div>
       <div><span>Trap to avoid</span><p>${escapeHtml(glance.biggestTrap || brief.caution || 'Do not treat first-pass judgement as final truth.')}</p></div>
     </section>
+    ${renderFirstScreen(brief.firstScreen || {})}
     ${renderDecisionReceipt(brief.decisionReceipt || {})}
     ${renderSourceTrace(glance.sourceTrace || {})}