Enhance Dockerfile and Redis configuration for improved build-time handling

- Added environment variables in Dockerfile for build-time placeholders, ensuring proper static analysis during the build process.
- Updated Redis initialization in redis.ts to include lazy connection, preventing network access during module import and improving error handling with a console log for connection errors.

apps/webui/src/lib/redis.ts

@@ -3,8 +3,19 @@ import { env } from './env';
 
 const globalForRedis = globalThis as unknown as { __nexumiRedis?: Redis };
 
-export const redis: Redis = globalForRedis.__nexumiRedis ?? new Redis(env.REDIS_URL, {
-  maxRetriesPerRequest: 3
+export const redis: Redis =
+  globalForRedis.__nexumiRedis ??
+  new Redis(env.REDIS_URL, {
+    maxRetriesPerRequest: 3,
+    // Defer the actual TCP connection until the first command is issued.
+    // This keeps module import side-effect free, which matters for
+    // Next.js's build-time "collect page data" step (no network access
+    // there) and avoids unhandled 'error' events on unreachable hosts.
+    lazyConnect: true
+  });
+
+redis.on('error', (error) => {
+  console.error('[redis]', error.message);
 });
 
 if (env.NODE_ENV !== 'production') {