Add the AI Agent Economy Stack as a standalone page

HAL 8's capability, economic and trust planes, the architecture stack,
standards alignment and the Buzz / HAL 8 / Vector ecosystem, re-set in the
hub's design language: the hub's :root tokens, Space Grotesk and JetBrains
Mono, section numbers, cards and corner-tick frames. Every logo is the
owner's official mark embedded as an inline SVG sprite, so the page has no
asset dependencies and can be folded into the bundled page later.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

README.md

@@ -10,6 +10,15 @@ bundled inside it. Sections: ecosystem overview, the Vector edge, tri-chain
 architecture, AP3X across ecosystems, markets, stack map, HAL 8, news,
 wallets, bridges, dapps, explorers, staking, developers, exchanges.
 
+## Standalone pages
+
+`agent-economy-stack.html` — "The AI Agent Economy Stack" (HAL 8's capability,
+economic and trust planes, architecture stack, standards and ecosystem) set in
+the hub's design language, served at `/agent-economy-stack.html`. Plain HTML
+with the hub's `:root` tokens and every logo embedded inline as SVG, so it can
+later be folded into the bundled page as a section. Fonts come from Google
+Fonts like the hub. Third-party marks are the owners' official files.
+
 ## How it is served
 
 Caddy on the HAL 8 host serves this directory as a static site. The box