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/tailwindcss/scripts/release-notes.js

@@ -0,0 +1,21 @@
+// Given a version, figure out what the release notes are so that we can use this to pre-fill the
+// relase notes on a GitHub release for the current version.
+
+let path = require('path')
+let fs = require('fs')
+
+let version =
+  process.argv[2] || process.env.npm_package_version || require('../package.json').version
+
+let changelog = fs.readFileSync(path.resolve(__dirname, '..', 'CHANGELOG.md'), 'utf8')
+let match = new RegExp(
+  `## \\[${version}\\] - (.*)\\n\\n([\\s\\S]*?)\\n(?:(?:##\\s)|(?:\\[))`,
+  'g'
+).exec(changelog)
+
+if (match) {
+  let [, , notes] = match
+  console.log(notes.trim())
+} else {
+  console.log(`Placeholder release notes for version: v${version}`)
+}