Give it a container and a page of its own

A Dockerfile that builds the bundle and serves it from nginx, matching the
three games already on the site, and the metadata a page needs when it is
somewhere rather than on a laptop: canonical, Open Graph, the two JSON-LD
blocks, and a noscript that describes the game rather than showing an empty
div to anybody who does not run scripts.

No dev proxy, unlike its siblings. They post scores to a shared service and
this one has nothing to post: a game of Diplomacy is not a number, and a
leaderboard reading "reached eleven centres" would be a worse thing to know
about somebody than nothing at all.

The favicon is seven powers round a board in the seven colours the map uses,
with the one supply centre in the middle they are all looking at -- drawn
here rather than drafted in a tool, like every other mark in this
repository.

And a way back out, absolute rather than "/": this is served from a
subdirectory in production and from the root in development, so the relative
answer is right in one of those and points at the game itself in the other.

vite.config.ts

@@ -4,21 +4,14 @@ import { defineConfig } from 'vite'
 // Vitest is left on its defaults on purpose: it already picks up *.test.ts and
 // nothing else, and importing `vitest/config` here drags in a second copy of
 // vite whose plugin types disagree with this one's.
+//
+// There is no dev proxy here, unlike this game's siblings. They post scores to
+// a shared service; this one has nothing to post. A game of Diplomacy is not a
+// number, and a leaderboard reading "reached eleven centres" would be a worse
+// thing to know about somebody than nothing at all.
 export default defineConfig({
   // Asset URLs are baked in at build time, so this has to match the path the
   // game is served from. Local development stays at the root.
   base: process.env.BASE_PATH ?? '/',
   plugins: [react()],
-  server: {
-    // The game talks to /api in every environment; in production that is
-    // nginx in front of the shared scores container. In development, run
-    // https://github.com/Coffey-Labs/games-scores alongside this -- or do not,
-    // and the board will say so rather than breaking.
-    proxy: {
-      '/api': {
-        target: process.env.SCORES_TARGET ?? 'http://localhost:5184',
-        changeOrigin: true,
-      },
-    },
-  },
 })