feat: image upload & preview untuk bug reports via MinIO

- Upload hingga 3 gambar per bug report (FileInput multi-select)
- Backend: POST /api/upload/image → MinIO, GET /api/bugs/images → presigned URL redirect
- Auto-create bucket jika belum ada saat server start
- Preview gambar fullscreen saat thumbnail diklik
- Diterapkan di /bug-reports dan /apps/$appId/errors
- Migrasi storage dari Seafile ke MinIO (minio SDK v8)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/lib/env.ts

@@ -17,4 +17,11 @@ export const env = {
   GOOGLE_CLIENT_SECRET: required('GOOGLE_CLIENT_SECRET'),
   SUPER_ADMIN_EMAILS: optional('SUPER_ADMIN_EMAIL', '').split(',').map(e => e.trim()).filter(Boolean),
   API_KEY: required('API_KEY'),
+  MINIO_ENDPOINT: required('MINIO_ENDPOINT'),
+  MINIO_PORT: parseInt(optional('MINIO_PORT', '443'), 10),
+  MINIO_USE_SSL: optional('MINIO_USE_SSL', 'true') === 'true',
+  MINIO_ACCESS_KEY: required('MINIO_ACCESS_KEY'),
+  MINIO_SECRET_KEY: required('MINIO_SECRET_KEY'),
+  MINIO_BUCKET: required('MINIO_BUCKET'),
+  MINIO_UPLOAD_DIR: optional('MINIO_UPLOAD_DIR', 'bug-reports'),
 } as const