chore: remove BackToTop component and scroll progress bar

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

components/BackToTop.tsx

@@ -1,45 +0,0 @@
-'use client';
-
-import { useState, useEffect, useRef } from 'react';
-import { ChevronUp } from 'lucide-react';
-
-export default function BackToTop() {
-  const [isVisible, setIsVisible] = useState(false);
-  const barRef = useRef<HTMLDivElement>(null);
-
-  useEffect(() => {
-    const onScroll = () => {
-      setIsVisible(window.scrollY > 300);
-      if (barRef.current) {
-        const el = document.documentElement;
-        const scrolled = el.scrollTop / (el.scrollHeight - el.clientHeight);
-        barRef.current.style.transform = `scaleX(${scrolled})`;
-      }
-    };
-    window.addEventListener('scroll', onScroll, { passive: true });
-    return () => window.removeEventListener('scroll', onScroll);
-  }, []);
-
-  return (
-    <>
-      {/* Scroll progress bar */}
-      <div
-        ref={barRef}
-        className="fixed top-0 left-0 right-0 h-px bg-primary z-50 origin-left"
-        style={{ transform: 'scaleX(0)', transition: 'transform 0.1s linear' }}
-      />
-
-      {/* Back to top button */}
-      {isVisible && (
-        <button
-          onClick={() => window.scrollTo({ top: 0, behavior: 'smooth' })}
-          className="fixed bottom-6 right-6 w-8 h-8 glass rounded-lg flex items-center justify-center text-muted-foreground/40 hover:text-primary hover:border-primary/40 transition-all duration-200 z-40"
-          aria-label="Back to top"
-          style={{ animation: 'fadeIn 0.2s ease-out both' }}
-        >
-          <ChevronUp className="w-3.5 h-3.5" />
-        </button>
-      )}
-    </>
-  );
-}