feat: distribute animated DrillBitSpinner across all major components as a background watermark

Former-commit-id: ad28a5d93b773be795cd0d73fd6ed2accd257a10

components/blocks/HeroSection.tsx

@@ -4,6 +4,7 @@ import Reveal from '@/components/Reveal';
 import { Badge, Container, Heading } from '@/components/ui';
 import { Button } from '@/components/ui/Button';
 import { DrillOrbit } from '@/components/ui/decorations/DrillOrbit';
+import { DrillBitSpinner } from '@/components/ui/decorations/DrillBitSpinner';
 
 export interface HeroSectionProps {
   title: string;
@@ -71,6 +72,10 @@ export const HeroSection: React.FC<HeroSectionProps> = (props) => {
             )}
           </div>
         </Container>
+        {/* Decorative: large abstract drill bit spinning slowly in background */}
+        <div className="absolute top-1/2 -translate-y-1/2 -right-48 md:-right-64 pointer-events-none opacity-[0.03]">
+          <DrillBitSpinner size={800} duration={20} glow={false} />
+        </div>
         {/* Decorative: abstract HDD bore trajectory */}
         <DrillOrbit side="right" />
       </section>