Add developer launch kit for Vestige v2.1.23

Dual-wave marketing assets (Receipt Lock + cognitive memory), GitHub Pages
landing, comparison doc, ready-to-post copy, growth-engine scripts, and a
dedicated marketing Vestige data-dir setup path.

Co-authored-by: Cursor <cursoragent@cursor.com>

.github/workflows/pages.yml

@@ -0,0 +1,46 @@
+name: Deploy GitHub Pages
+
+on:
+  push:
+    branches: [main]
+    paths:
+      - 'docs/website/**'
+      - 'docs/marketing/assets/**'
+      - '.github/workflows/pages.yml'
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+concurrency:
+  group: pages
+  cancel-in-progress: false
+
+jobs:
+  deploy:
+    runs-on: ubuntu-latest
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Prepare site root
+        run: |
+          mkdir -p _site
+          cp -r docs/website/* _site/
+          mkdir -p _site/assets
+          cp -r docs/marketing/assets/* _site/assets/ 2>/dev/null || true
+          # Fix asset paths for Pages (no parent ../)
+          sed -i 's|../marketing/assets/|assets/|g' _site/index.html || true
+
+      - uses: actions/configure-pages@v5
+
+      - uses: actions/upload-pages-artifact@v3
+        with:
+          path: _site
+
+      - id: deployment
+        uses: actions/deploy-pages@v4