dashboard: 3-column layout — swarm / 0per4t0r 1n / m3ss4g3s

regroups the 7 stacked sections into three semantic columns
backed by a CSS grid (single column under 1400px, 3 columns
above). column headers are sticky so vertical scrolling
inside a column doesn't lose context.

- SW4RM (left, slightly wider): containers + kept-state +
  spawn-agent form + meta-input update form. all
  swarm-mutating operator knobs live here.
- 0PER4T0R 1N (middle): mind-questions + pending approvals.
  the two things waiting on operator action.
- M3SS4G3S (right): operator-inbox + msg-flow tail + the
  @-mention compose box. broker traffic in one place.

spawn form moves out of renderApprovals into static HTML
under sw4rm; renderApprovals no longer injects it.

cosmetic: per-section h2/divider replaced with smaller cyan
sub-heads + a dashed underline so each column reads as one
cohesive unit instead of seven competing banners. body
max-width grows 70em → 110em to actually use the new
horizontal real estate.

hive-c0re/assets/app.js

@@ -606,23 +606,6 @@
     const root = $('approvals-section');
     root.innerHTML = '';
 
-    // Spawn request form: submitting it queues a Spawn approval that
-    // lands in this same list, so the form belongs here rather than on
-    // the containers list (the agent doesn't exist yet).
-    const spawn = el('form', {
-      method: 'POST', action: '/request-spawn',
-      class: 'spawnform', 'data-async': '',
-    });
-    spawn.append(
-      el('input', {
-        name: 'name',
-        placeholder: 'new agent name (≤9 chars)',
-        maxlength: '9', required: '', autocomplete: 'off',
-      }),
-      el('button', { type: 'submit', class: 'btn btn-spawn' }, '◆ R3QU3ST SP4WN'),
-    );
-    root.append(spawn);
-
     const history = s.approval_history || [];
     const active = localStorage.getItem(APPROVAL_TAB_KEY) || 'pending';
     const tabs = el('div', { class: 'approval-tabs' });