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/json5/lib/util.js

@@ -0,0 +1,35 @@
+const unicode = require('../lib/unicode')
+
+module.exports = {
+    isSpaceSeparator (c) {
+        return typeof c === 'string' && unicode.Space_Separator.test(c)
+    },
+
+    isIdStartChar (c) {
+        return typeof c === 'string' && (
+            (c >= 'a' && c <= 'z') ||
+        (c >= 'A' && c <= 'Z') ||
+        (c === '$') || (c === '_') ||
+        unicode.ID_Start.test(c)
+        )
+    },
+
+    isIdContinueChar (c) {
+        return typeof c === 'string' && (
+            (c >= 'a' && c <= 'z') ||
+        (c >= 'A' && c <= 'Z') ||
+        (c >= '0' && c <= '9') ||
+        (c === '$') || (c === '_') ||
+        (c === '\u200C') || (c === '\u200D') ||
+        unicode.ID_Continue.test(c)
+        )
+    },
+
+    isDigit (c) {
+        return typeof c === 'string' && /[0-9]/.test(c)
+    },
+
+    isHexDigit (c) {
+        return typeof c === 'string' && /[0-9A-Fa-f]/.test(c)
+    },
+}