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/autoprefixer/lib/hacks/file-selector-button.js

@@ -0,0 +1,26 @@
+let Selector = require('../selector')
+let utils = require('../utils')
+
+class FileSelectorButton extends Selector {
+  constructor(name, prefixes, all) {
+    super(name, prefixes, all)
+
+    if (this.prefixes) {
+      this.prefixes = utils.uniq(this.prefixes.map(() => '-webkit-'))
+    }
+  }
+
+  /**
+   * Return different selectors depend on prefix
+   */
+  prefixed(prefix) {
+    if (prefix === '-webkit-') {
+      return '::-webkit-file-upload-button'
+    }
+    return `::${prefix}file-selector-button`
+  }
+}
+
+FileSelectorButton.names = ['::file-selector-button']
+
+module.exports = FileSelectorButton