Module envelope 

JSON success/error envelopes for agents. JSON envelope helpers (schema_version = 1).

Success and error envelopes are written to stdout for agent parsing. Human diagnostics stay on stderr.

Success shape

{"schema_version":1,"ok":true,"data":{}}

Error shape

{"schema_version":1,"ok":false,"error":{"kind":"unavailable","message":"...","exit_code":69}}

Functions

print_error_json

Print an error envelope derived from CliError.

print_success_json

Print a success envelope with arbitrary JSON data and flush a single line.