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/@nodelib/fs.walk/out/providers/stream.d.ts

@@ -0,0 +1,12 @@
+/// <reference types="node" />
+import { Readable } from 'stream';
+import AsyncReader from '../readers/async';
+import type Settings from '../settings';
+export default class StreamProvider {
+    private readonly _root;
+    private readonly _settings;
+    protected readonly _reader: AsyncReader;
+    protected readonly _stream: Readable;
+    constructor(_root: string, _settings: Settings);
+    read(): Readable;
+}