perf: eliminate global JS bloat and defer autoPlay video

- Dynamically imported ToolCoordinator dependencies
- Removes ~400KB from global layout (html2canvas, framer-motion)
- Implemented IntersectionObserver in VideoSection
- Prevents 1.8MB .webm autoPlay blocking initial network
- Restored SSR hydration visibility for LCP elements in Hero

components/record-mode/ToolCoordinator.tsx

@@ -2,8 +2,17 @@
 
 import React, { useState, useEffect } from 'react';
 import { useRecordMode } from './RecordModeContext';
-import { FeedbackOverlay } from '@mintel/next-feedback/FeedbackOverlay';
-import { RecordModeOverlay } from './RecordModeOverlay';
+import dynamic from 'next/dynamic';
+
+const FeedbackOverlay = dynamic(
+  () => import('@mintel/next-feedback/FeedbackOverlay').then((mod) => mod.FeedbackOverlay),
+  { ssr: false },
+);
+
+const RecordModeOverlay = dynamic(
+  () => import('./RecordModeOverlay').then((mod) => mod.RecordModeOverlay),
+  { ssr: false },
+);
 import { PickingHelper } from './PickingHelper';
 
 interface ToolCoordinatorProps {