fix: never cache HTML so deploys always serve current chunks

Anonymous HTML was sent with 'public, max-age=60, s-maxage=300,
stale-while-revalidate=300'. After a rebuild the old chunk URLs (keyed by
deploy id) are deleted, so any browser/CDN holding the stale HTML got 404s
for up to five minutes. Since the deploy id is the git commit, the HTML must
be re-fetched after every deploy; only content-hashed static assets should
be cached. Return no-store for all HTML documents.

src/proxy.ts

@@ -40,17 +40,14 @@ export const proxy = async (req: import("next/server").NextRequest) => {
 
 	const response = NextResponse.next({ request: { headers } });
 
-	if (token) {
-		response.headers.set(
-			"Cache-Control",
-			"private, no-cache, no-store, max-age=0, must-revalidate",
-		);
-	} else {
-		response.headers.set(
-			"Cache-Control",
-			"public, max-age=60, s-maxage=300, stale-while-revalidate=300",
-		);
-	}
+	// HTML is never cached (browser/CDN/edge) so that after a deploy the page
+	// always references the current build's chunks. Static assets are
+	// content-hashed + immutable and can be cached aggressively; a stale HTML
+	// document would reference chunk URLs that no longer exist after a rebuild.
+	response.headers.set(
+		"Cache-Control",
+		"private, no-cache, no-store, max-age=0, must-revalidate",
+	);
 
 	for (const [key, value] of Object.entries(SECURITY_HEADERS)) {
 		response.headers.set(key, value);