agent ui: input lives in terminal section, banner shimmer on activity

agent page restructure:
- send form moves into the terminal panel as a prompt-style row beneath
  the live tail (status line stays above so it still reads as a header).
- live panel + prompt share a single bordered 'terminal-wrap' box.
- harness-alive / login-state status lines drop their decorative ascii
  bookends; just a leading dot/glyph remains.
- banner gradient is now a real css gradient with a shimmer animation
  toggled by an .active class. turn_start adds it, turn_end removes it.
  dashboard side mirrors this: each broker sse event nudges a 4s
  shimmer window.
- dashboard container rows drop their static ▓█▓▒░ / ▒░▒░░ glyph
  prefixes; the role chips already disambiguate m1nd vs ag3nt.
- empty-state placeholders drop the ▓ bookends.

terminal pre-fill: hive-ag3nt::events::Bus grows a 500-event ring
buffer; new GET /events/history endpoint returns it. The agent JS
fetches history before opening the SSE stream so opening the page mid-
turn shows the last N events instead of a blank panel. The replay
walks turn_start/turn_end pairs to seed the banner-active state
correctly if a turn was still open.

hive-c0re/assets/app.js

@@ -114,7 +114,7 @@
     }
 
     if (!s.containers.length && !s.transients.length) {
-      root.append(el('p', { class: 'empty' }, '▓ no managed containers ▓'));
+      root.append(el('p', { class: 'empty' }, 'no managed containers'));
       return;
     }
 
@@ -123,8 +123,6 @@
       const url = `http://${s.hostname}:${c.port}/`;
       const li = el('li');
       li.append(
-        el('span', { class: 'glyph' }, c.is_manager ? '▓█▓▒░' : '▒░▒░░'),
-        ' ',
         el('a', { href: url }, c.name),
         ' ',
         el('span', { class: c.is_manager ? 'role role-m1nd' : 'role role-ag3nt' },
@@ -180,7 +178,7 @@
     const root = $('questions-section');
     root.innerHTML = '';
     if (!s.questions || !s.questions.length) {
-      root.append(el('p', { class: 'empty' }, '▓ no pending questions ▓'));
+      root.append(el('p', { class: 'empty' }, 'no pending questions'));
       return;
     }
     const fmt = (n) => new Date(n * 1000).toISOString().replace('T', ' ').slice(0, 19);
@@ -223,7 +221,7 @@
     const root = $('inbox-section');
     root.innerHTML = '';
     if (!s.operator_inbox || !s.operator_inbox.length) {
-      root.append(el('p', { class: 'empty' }, '▓ no messages ▓'));
+      root.append(el('p', { class: 'empty' }, 'no messages'));
       return;
     }
     const fmt = (n) => new Date(n * 1000).toISOString().replace('T', ' ').slice(0, 19);
@@ -245,7 +243,7 @@
     const root = $('approvals-section');
     root.innerHTML = '';
     if (!s.approvals.length) {
-      root.append(el('p', { class: 'empty' }, '▓ queue empty ▓'));
+      root.append(el('p', { class: 'empty' }, 'queue empty'));
       return;
     }
     const ul = el('ul', { class: 'approvals' });
@@ -321,9 +319,21 @@
     const es = new EventSource('/messages/stream');
     const MAX_ROWS = 200;
     const tsFmt = (n) => new Date(n * 1000).toISOString().slice(11, 19);
+    // Animate the banner whenever a broker event lands. Each event nudges
+    // the shimmer window; if traffic stops, the class falls off after the
+    // grace timer.
+    const banner = document.querySelector('.banner');
+    let bannerOffTimer = null;
+    function pulseBanner() {
+      if (!banner) return;
+      banner.classList.add('active');
+      if (bannerOffTimer) clearTimeout(bannerOffTimer);
+      bannerOffTimer = setTimeout(() => banner.classList.remove('active'), 4000);
+    }
     es.onmessage = (e) => {
       let m;
       try { m = JSON.parse(e.data); } catch { return; }
+      pulseBanner();
       // Live-update the inbox when claude sends to operator.
       if (m.kind === 'sent' && m.to === 'operator') refreshState();
       const row = document.createElement('div');