Optimize app: Improve SEO, Accessibility, and Performance

**SEO:**
- Added meta description and updated page title in [index.html] to improve search engine visibility.

**Accessibility:**
- Improved color contrast across multiple components (`TechnicalIndicators`, `PriceDisplay`, `MarketIndicators`, `CandleChart`, `ATRIndicator`) to meet WCAG AA standards.
- Fixed missing form label in `ThemeToggle` by adding `aria-label` and wrapping the switch in a label element with screen-reader-only text.

**Performance:**
- Resized crypto icons in `public/crypto-icons` to 48x48px to reduce file size and improve load times.

**Maintenance:**
- Added PowerShell scripts (`resize_images.ps1`, `check_images.ps1`) for image optimization and verification.

Author: patrickcmserrano

index.html

@@ -4,7 +4,8 @@
     <meta charset="utf-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1" />
     <link rel="icon" type="image/x-icon" href="/favicon.ico" />
-    <title>bitcointracker</title>
+    <title>BitcoinTracker - Real-time Crypto Tracking & Analysis</title>
+    <meta name="description" content="Track real-time Bitcoin and cryptocurrency prices, analyze market trends with technical indicators, and get trading insights with BitcoinTracker." />
     <script>
       // Aplicar tema imediatamente no carregamento inicial
       try {

public/crypto-icons/bitcoin.png

@@ -63,7 +63,7 @@
   <div class="space-y-2">
     {#if atr14Daily !== undefined}
       <div class="flex items-baseline gap-2">
-        <span class="text-2xl font-bold text-primary-600-300-token">
+        <span class="text-2xl font-bold text-primary-700 dark:text-primary-300">
           ${formatATR(atr14Daily)}
         </span>
         <span class="text-sm text-surface-600-300-token">

public/crypto-icons/ethereum.png

@@ -18,9 +18,9 @@
 
   // Função para obter cor da variação percentual
   function getPercentChangeColor(change: number): string {
-    if (change > 0) return 'text-success-500';
-    if (change < 0) return 'text-error-500';
-    return 'text-gray-500';
+    if (change > 0) return 'text-green-700 dark:text-green-400';
+    if (change < 0) return 'text-red-700 dark:text-red-400';
+    return 'text-gray-600 dark:text-gray-400';
   }
 
   // Função para obter dados do timeframe ativo
@@ -180,14 +180,14 @@
   .crypto-name {
     font-size: 1rem;
     font-weight: 800;
-    color: var(--crypto-color);
+    color: var(--color-surface-700);
     text-transform: uppercase;
     letter-spacing: 0.5px;
     text-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
   }
 
   :global(.dark) .crypto-name {
-    color: var(--crypto-color);
+    color: var(--color-surface-200);
     text-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
   }