feat(docker): prepare portable images with runtime hotel configuration

src/lib/runtime-asset-config.ts

@@ -0,0 +1,47 @@
+import "server-only";
+
+// Dynamic lookup keeps legacy NEXT_PUBLIC aliases out of build-time inlining.
+function setting(name: string): string | undefined {
+	return process.env[name]?.trim() || undefined;
+}
+
+export function resolveImagerBase(origin?: string): string {
+	const base =
+		setting("IMAGER_URL") ||
+		setting("NEXT_PUBLIC_IMAGER_URL") ||
+		setting("IMAGING_UPSTREAM_URL") ||
+		"https://www.habbo.com/habbo-imaging/avatarimage";
+	const target = new URL(base, origin);
+	const ownOrigins = new Set([origin]);
+	const appUrl = setting("APP_URL");
+	if (appUrl) ownOrigins.add(new URL(appUrl).origin);
+	if (!["http:", "https:"].includes(target.protocol))
+		throw new Error("Invalid imager URL protocol");
+	if (
+		ownOrigins.has(target.origin) &&
+		["/imaging", "/api/imaging/avatar"].includes(
+			target.pathname.replace(/\/+$/, ""),
+		)
+	) {
+		const upstream = setting("IMAGING_UPSTREAM_URL");
+		if (!upstream)
+			throw new Error(
+				"IMAGING_UPSTREAM_URL is required when the imager points to the CMS proxy",
+			);
+		const resolved = new URL(upstream);
+		if (
+			!["http:", "https:"].includes(resolved.protocol) ||
+			(ownOrigins.has(resolved.origin) &&
+				["/imaging", "/api/imaging/avatar"].includes(
+					resolved.pathname.replace(/\/+$/, ""),
+				))
+		)
+			throw new Error("Imager configuration creates a proxy loop");
+		return resolved.href.replace(/\/+$/, "");
+	}
+	return target.href.replace(/\/+$/, "");
+}
+
+export function resolveBadgeBase(): string | undefined {
+	return setting("BADGE_URL") || setting("NEXT_PUBLIC_BADGE_URL");
+}