The masthead wears its deploy stamp

A small yyyy.mm.dd.hh.mm mark beside the edition line, baked in at
build time — and the deploy builds moments before it ships, so the
stamp reads as deploy time.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015RCWSTnb1KYTPyL4GmhGnF

packages/web/src/vite-env.d.ts

@@ -0,0 +1,5 @@
+/// <reference types="vite/client" />
+/// <reference types="svelte" />
+
+/** Build moment, yyyy.mm.dd.hh.mm — injected by vite.config.ts. */
+declare const __BUILD_STAMP__: string;