Hcl Fmt Stdin Check And Diff

hcl fmt --stdin honors --check and --diff

terragrunt hcl fmt --stdin ignored --check and --diff. It printed the reformatted HCL and exited 0 whether or not the input needed formatting.

--check now exits with status code 1 when the input needs formatting, and --diff prints a unified diff labeled old/stdin and new/stdin. Neither flag prints the formatted content, so getting that content back means running --stdin without them.