fix: SearXNG startup + update README logo and favicon

- Fix SearXNG limiter.toml directory issue by creating file at container
  startup via entrypoint command (rm -rf then recreate)
- Update README to use logo.svg instead of logo.png
- Redesign favicon.svg to match main logo style:
  - Same gold-to-green gradient background
  - Line gradient from white to green
  - Glow effect on chart line
  - Decorative dots at data points
  - Green arrow indicator

frontend/public/favicon.svg

@@ -2,10 +2,49 @@
   <defs>
     <linearGradient id="bgGrad" x1="0%" y1="0%" x2="100%" y2="100%">
       <stop offset="0%" style="stop-color:#D4AF37"/>
+      <stop offset="50%" style="stop-color:#C5A028"/>
       <stop offset="100%" style="stop-color:#22C55E"/>
     </linearGradient>
+    <linearGradient id="lineGrad" x1="0%" y1="0%" x2="100%" y2="0%">
+      <stop offset="0%" style="stop-color:#FFFFFF;stop-opacity:0.9"/>
+      <stop offset="100%" style="stop-color:#22C55E"/>
+    </linearGradient>
+    <filter id="glow">
+      <feGaussianBlur stdDeviation="0.5" result="blur"/>
+      <feMerge>
+        <feMergeNode in="blur"/>
+        <feMergeNode in="SourceGraphic"/>
+      </feMerge>
+    </filter>
   </defs>
-  <rect x="1" y="1" width="30" height="30" rx="6" fill="url(#bgGrad)"/>
-  <path d="M 6 20 Q 10 16, 14 18 Q 18 20, 22 12 L 26 8" fill="none" stroke="#FFF" stroke-width="2.5" stroke-linecap="round"/>
-  <path d="M 23 10 L 26 8 L 26 12" fill="none" stroke="#22C55E" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
+
+  <!-- Background -->
+  <rect x="1" y="1" width="30" height="30" rx="5" fill="url(#bgGrad)"/>
+
+  <!-- Chart line with glow -->
+  <g filter="url(#glow)">
+    <path
+      d="M 5 21 Q 9 18, 12 19 Q 15 20, 18 15 Q 21 10, 24 11 L 27 7"
+      fill="none"
+      stroke="url(#lineGrad)"
+      stroke-width="2.5"
+      stroke-linecap="round"
+      stroke-linejoin="round"
+    />
+    <!-- Arrow -->
+    <path
+      d="M 24.5 9 L 27 7 L 27 10.5"
+      fill="none"
+      stroke="#22C55E"
+      stroke-width="2"
+      stroke-linecap="round"
+      stroke-linejoin="round"
+    />
+  </g>
+
+  <!-- Dots on the line -->
+  <circle cx="5" cy="21" r="1.5" fill="#FFFFFF" opacity="0.9"/>
+  <circle cx="12" cy="19" r="1.2" fill="#FFFFFF" opacity="0.8"/>
+  <circle cx="18" cy="15" r="1.2" fill="#FFFFFF" opacity="0.8"/>
+  <circle cx="27" cy="7" r="1.8" fill="#22C55E"/>
 </svg>