Update media-server: Vinyl record mode and accent color picker

- Vinyl mode: album art as center label with grooves, spindle hole, vignette
- Smooth transition between normal and vinyl modes
- Accent color picker with 9 preset colors in header
- Fix progress bar hover layout shift (use scaleY instead of height)
- Fix glow position jump when toggling vinyl mode

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

media_server/static/index.html

@@ -66,6 +66,12 @@
                 <span class="version-label" id="version-label"></span>
             </div>
             <div style="display: flex; align-items: center; gap: 0.5rem;">
+                <div class="accent-picker">
+                    <button class="accent-picker-btn" onclick="toggleAccentPicker()" title="Accent color">
+                        <span class="accent-dot" id="accentDot"></span>
+                    </button>
+                    <div class="accent-picker-dropdown" id="accentDropdown"></div>
+                </div>
                 <button class="theme-toggle" onclick="toggleTheme()" data-i18n-title="player.theme" title="Toggle theme" id="theme-toggle">
                     <svg id="theme-icon-sun" viewBox="0 0 24 24" style="display: none;">
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