docs(design): remove SVG, use PNG logo only

SVG icon is no longer in use. public/logo.png (1024x1024 RGBA) is
the single logo asset. DESIGN.md updated accordingly: SVG snippet
removed, wordmark pattern and <head> references updated to PNG.

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

node_modules/@heroicons/react/24/outline/esm/UserCircleIcon.js

@@ -0,0 +1,26 @@
+import * as React from "react";
+function UserCircleIcon({
+  title,
+  titleId,
+  ...props
+}, svgRef) {
+  return /*#__PURE__*/React.createElement("svg", Object.assign({
+    xmlns: "http://www.w3.org/2000/svg",
+    fill: "none",
+    viewBox: "0 0 24 24",
+    strokeWidth: 1.5,
+    stroke: "currentColor",
+    "aria-hidden": "true",
+    "data-slot": "icon",
+    ref: svgRef,
+    "aria-labelledby": titleId
+  }, props), title ? /*#__PURE__*/React.createElement("title", {
+    id: titleId
+  }, title) : null, /*#__PURE__*/React.createElement("path", {
+    strokeLinecap: "round",
+    strokeLinejoin: "round",
+    d: "M17.982 18.725A7.488 7.488 0 0 0 12 15.75a7.488 7.488 0 0 0-5.982 2.975m11.963 0a9 9 0 1 0-11.963 0m11.963 0A8.966 8.966 0 0 1 12 21a8.966 8.966 0 0 1-5.982-2.275M15 9.75a3 3 0 1 1-6 0 3 3 0 0 1 6 0Z"
+  }));
+}
+const ForwardRef = /*#__PURE__*/ React.forwardRef(UserCircleIcon);
+export default ForwardRef;