feat(webapp): add installable PWA support

WebApp/static/icons/phonecam-icon.svg

@@ -0,0 +1,16 @@
+<svg width="512" height="512" viewBox="0 0 512 512" fill="none" xmlns="http://www.w3.org/2000/svg">
+  <rect width="512" height="512" rx="120" fill="#0A0A0C"/>
+  <rect x="84" y="84" width="344" height="344" rx="92" fill="url(#bg)"/>
+  <rect x="116" y="132" width="280" height="248" rx="48" fill="#15161D" stroke="rgba(255,255,255,0.08)" stroke-width="8"/>
+  <rect x="146" y="164" width="220" height="160" rx="28" fill="#0E1016"/>
+  <circle cx="256" cy="244" r="52" fill="#2563EB"/>
+  <circle cx="256" cy="244" r="28" fill="#0A0A0C"/>
+  <path d="M186 122C186 108.745 196.745 98 210 98H302C315.255 98 326 108.745 326 122V144H186V122Z" fill="#2563EB"/>
+  <path d="M220 290L256 326L322 214" stroke="white" stroke-width="20" stroke-linecap="round" stroke-linejoin="round"/>
+  <defs>
+    <linearGradient id="bg" x1="84" y1="84" x2="428" y2="428" gradientUnits="userSpaceOnUse">
+      <stop stop-color="#1D4ED8"/>
+      <stop offset="1" stop-color="#1E40AF"/>
+    </linearGradient>
+  </defs>
+</svg>