feat: v1.13.0 — SVG Logo, Marquee, Player UX, Global Shortcuts fix

### Added
- SVG logo with theme-adaptive gradient in sidebar (full wordmark + P-icon for collapsed state)
- Player bar: song title/artist marquee scroll on overflow
- Player bar: live volume percentage tooltip on slider hover

### Changed
- Sidebar collapse button moved to right-edge hover tab
- Player bar: fixed 320px track info width, increased waveform margins
- Settings: Server tab opens by default
- Crossfade: experimental badge removed (stable)
- Help page: Lyrics/Keybindings/Font entries added, theme count corrected

### Fixed
- Global shortcuts double-fire (Rust-side ShortcutMap idempotency fix)
- W98 theme: comprehensive contrast fixes for navy hover backgrounds
- Help page: removed orphaned translation key under Playback

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

src/components/MarqueeText.tsx

@@ -0,0 +1,49 @@
+import React, { useRef, useState, useEffect, useCallback } from 'react';
+
+interface Props {
+  text: string;
+  className?: string;
+  style?: React.CSSProperties;
+  onClick?: () => void;
+}
+
+export default function MarqueeText({ text, className, style, onClick }: Props) {
+  const containerRef = useRef<HTMLDivElement>(null);
+  const textRef = useRef<HTMLSpanElement>(null);
+  const [scrollAmount, setScrollAmount] = useState(0);
+
+  const measure = useCallback(() => {
+    const container = containerRef.current;
+    const text = textRef.current;
+    if (!container || !text) return;
+    text.style.display = 'inline-block';
+    const textWidth = text.getBoundingClientRect().width;
+    text.style.display = '';
+    const overflow = textWidth - container.clientWidth;
+    setScrollAmount(overflow > 4 ? Math.ceil(overflow) : 0);
+  }, []);
+
+  useEffect(() => {
+    measure();
+    const ro = new ResizeObserver(measure);
+    if (containerRef.current) ro.observe(containerRef.current);
+    return () => ro.disconnect();
+  }, [text, measure]);
+
+  return (
+    <div
+      ref={containerRef}
+      className={`marquee-wrap${className ? ` ${className}` : ''}`}
+      style={style}
+      onClick={onClick}
+    >
+      <span
+        ref={textRef}
+        className={scrollAmount > 0 ? 'marquee-scroll' : ''}
+        style={scrollAmount > 0 ? { '--marquee-amount': `-${scrollAmount}px` } as React.CSSProperties : {}}
+      >
+        {text}
+      </span>
+    </div>
+  );
+}