A single-file bash script that masks sensitive values in a .env-style
file so you can safely paste it into a bug report, CI log, chat message, or
gist — without leaking secrets. Keys are never touched. Non-sensitive values
(PORT=3000, NODE_ENV=production, ...) are left alone too — only values
belonging to sensitive-looking keys get masked.
DB_PASSWORD="hunter2" -> DB_PASSWORD=""