Presigned URL API

Stateless microservice that generates time-limited pre-signed AWS S3 URLs for secure file uploads, used by the Dashboard for document uploads (KYC, title deeds) and the City Builder for asset uploads. Each URL expires after 15 minutes and is scoped to a specific S3 path. If down, all file upload workflows across the platform fail silently — users see upload buttons but files never reach S3. Contact Parth for S3 bucket configuration or CORS issues.