refactor: full DDD + Clean Architecture refactor

- Hapus src/utils/ (17 files) + src/db/ (8 files) dead code
- Absorb 7 re-export stubs → real impl di lokasi DDD
- Buat src/infrastructure/di.ts (DI container)
- Rewrite 5 controllers pakai repository/DI
- Fix shared/utils imports, env.ts, routes, index.ts
- Update package.json build path migrate
- Lint clean, build clean

src/interfaces/s3/virtual-host.ts

@@ -1 +1,27 @@
-export { extractS3BucketFromHost } from '../../utils/s3/virtual-host';
+const stripPort = (host: string): string => {
+  // Handle IPv6: [::1]:8080 -> [::1]
+  if (host.startsWith('[')) {
+    const closeBracket = host.indexOf(']');
+    return host.slice(0, closeBracket + 1).toLowerCase();
+  }
+  return host.split(':')[0].toLowerCase().replace(/\.$/, '');
+};
+
+const isValidBucketLabel = (bucket: string): boolean =>
+  /^[a-z0-9][a-z0-9.-]{1,61}[a-z0-9]$/.test(bucket) &&
+  !bucket.includes('..') &&
+  !bucket.includes('.-') &&
+  !bucket.includes('-.');
+
+export const extractS3BucketFromHost = (host: string, domains: string[]): string | null => {
+  const normalizedHost = stripPort(host);
+  for (const domain of domains) {
+    const normalizedDomain = stripPort(domain);
+    if (!normalizedDomain || normalizedHost === normalizedDomain) continue;
+    if (!normalizedHost.endsWith(`.${normalizedDomain}`)) continue;
+
+    const bucket = normalizedHost.slice(0, -(normalizedDomain.length + 1));
+    return isValidBucketLabel(bucket) ? bucket : null;
+  }
+  return null;
+};