Backend optimizations, frontend optimizations, and UI design improvements

Backend optimizations:
- GZip middleware for compressed responses
- Concurrent WebSocket broadcast
- Skip status polling when no clients connected
- Deduplicated token validation with caching
- Fire-and-forget HA state callbacks
- Single stat() per browser item
- Metadata caching (LRU)
- M3U playlist optimization
- Autostart setup (Task Scheduler + hidden VBS launcher)

Frontend code optimizations:
- Fix thumbnail blob URL memory leak
- Fix WebSocket ping interval leak on reconnect
- Skip artwork re-fetch when same track playing
- Deduplicate volume slider logic
- Extract magic numbers into named constants
- Standardize error handling with toast notifications
- Cache play/pause SVG constants
- Loading state management for async buttons
- Request deduplication for rapid clicks
- Cache 30+ DOM element references
- Deduplicate volume updates over WebSocket

Frontend design improvements:
- Progress bar seek thumb and hover expansion
- Custom themed scrollbars
- Toast notification accent border strips
- Keyboard focus-visible states
- Album art ambient glow effect
- Animated sliding tab indicator
- Mini-player top progress line
- Empty state SVG illustrations
- Responsive tablet breakpoint (601-900px)
- Horizontal player layout on wide screens (>900px)
- Glassmorphism mini-player with backdrop blur
- Vinyl spin animation (toggleable)
- Table horizontal scroll on narrow screens

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

media_server/main.py

@@ -9,6 +9,7 @@ from pathlib import Path
 import uvicorn
 from fastapi import FastAPI, Request
 from fastapi.middleware.cors import CORSMiddleware
+from fastapi.middleware.gzip import GZipMiddleware
 from fastapi.responses import FileResponse
 from fastapi.staticfiles import StaticFiles
 
@@ -74,6 +75,9 @@ def create_app() -> FastAPI:
         lifespan=lifespan,
     )
 
+    # Compress responses > 1KB
+    app.add_middleware(GZipMiddleware, minimum_size=1000)
+
     # Add CORS middleware for cross-origin requests
     app.add_middleware(
         CORSMiddleware,