Force [hash] in Bun chunk naming so older Bun versions don't collide

Cloudflare Pages ships an older Bun than the one used locally. That
version emits shared CSS chunks via the default 'chunk-[hash]' naming
template, but the [hash] token isn't always populated when the chunk
is shared across multiple HTML entrypoints — every sub-page that
imports sub-pages.css ends up wanting the same './chunk-' filename
and the build aborts with 'Multiple files share the same output path'.

Pin the chunk and asset naming explicitly so [hash] is always present
regardless of Bun version.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

scripts/build.js

@@ -298,6 +298,16 @@ async function buildStaticSite(extraEntrypoints = []) {
       outdir: outdir,
       minify: true,
       sourcemap: 'linked',
+      // Older Bun versions (e.g. the one Cloudflare Pages ships) emit shared
+      // CSS/JS chunks without a content hash in the filename, which collides
+      // when multiple HTML entries import the same CSS partial. Force the
+      // chunk + asset naming to always include [hash] so the build is
+      // reproducible across Bun versions.
+      naming: {
+        entry: '[dir]/[name].[ext]',
+        chunk: '[name]-[hash].[ext]',
+        asset: '[name]-[hash].[ext]',
+      },
     });
 
     if (!result.success) {