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/reusify/eslint.config.js

@@ -0,0 +1,14 @@
+'use strict'
+
+const base = require('neostandard')({})
+
+module.exports = [
+  ...base,
+  {
+    name: 'old-standard',
+    rules: {
+      'no-var': 'off',
+      'object-shorthand': 'off',
+    }
+  }
+]