refactor(decnet_web/AttackerDetail): extract TimelineSection

Lift the TIMELINE collapsible (timestamps, ASN, reverse DNS,
leaked-IPs row with rotation detection) into its own section.
LeakedIPsRow + the rotation/inline-limit constants come along
since they were only ever used here.

Also moves the shared `Section` collapsible primitive into
AttackerDetail/ui.tsx so the remaining sections can adopt the
template without re-importing through the parent module.

- New AttackerDetail/sections/TimelineSection.tsx (LeakedIPsRow
  inline as a private helper)
- AttackerDetail/ui.tsx now exports both Tag and Section
- AttackerDetail.tsx loses LeakedIPsRow, the Section helper, the
  Timeline JSX block, and now-unused imports (ChevronUp, ChevronDown,
  AttackerData)
- TimelineSection.test.tsx covers timestamps, unknown-origin path,
  rotation badge, empty leaks, collapse, and toggle callback

decnet_web/src/components/AttackerDetail/ui.tsx

@@ -1,4 +1,5 @@
 import React from 'react';
+import { ChevronDown, ChevronUp } from '../../icons';
 
 /** Pill-style tag chip used throughout the AttackerDetail surface
  *  for badges, filters, and category labels. Color drives both the
@@ -20,3 +21,30 @@ export const Tag: React.FC<{ children: React.ReactNode; color?: string }> = ({
     {children}
   </span>
 );
+
+/** Collapsible panel used by every section on the AttackerDetail page.
+ *  The header is the toggle; an optional `right` slot hosts controls
+ *  (filters, action buttons) whose clicks are stopped from bubbling
+ *  to the toggle handler. */
+export const Section: React.FC<{
+  title: React.ReactNode;
+  right?: React.ReactNode;
+  open: boolean;
+  onToggle: () => void;
+  children: React.ReactNode;
+}> = ({ title, right, open, onToggle, children }) => (
+  <div className="logs-section">
+    <div
+      className="section-header"
+      style={{ justifyContent: 'space-between', cursor: 'pointer', userSelect: 'none' }}
+      onClick={onToggle}
+    >
+      <div style={{ display: 'flex', alignItems: 'center', gap: '8px' }}>
+        {open ? <ChevronUp size={16} className="dim" /> : <ChevronDown size={16} className="dim" />}
+        <h2>{title}</h2>
+      </div>
+      {right && <div onClick={(e) => e.stopPropagation()}>{right}</div>}
+    </div>
+    {open && children}
+  </div>
+);